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Background Gene dosage imbalance caused by copy number variations (CNVs) is a prominent contributor to brain disorders. In particular, 15q11.2 CNV duplications and deletions have been associated with autism spectrum disorder and schizophrenia, respectively. The mechanism underlying these diametric contributions remains unclear. Methods We established both loss-of-function and gain-of-function mouse models of Cyfip1, one of four genes within 15q11.2 CNVs. To assess the functional consequences of altered CYFIP1 levels, we performed systematic investigations on behavioral, electrophysiological, and biochemical phenotypes in both mouse models. In addition, we utilized RNA immunoprecipitation sequencing (RIP-seq) analysis to reveal molecular targets of CYFIP1 in vivo. Results Cyfip1 loss-of-function and gain-of function mouse models exhibited distinct and shared behavioral abnormalities related to autism spectrum disorder and schizophrenia. RIP-seq analysis identified messenger RNA targets of CYFIP1 in vivo, including postsynaptic NMDA receptor (NMDAR) complex components. In addition, these mouse models showed diametric changes in levels of postsynaptic NMDAR complex components at synapses because of dysregulated protein translation, resulting in bidirectional alteration of NMDAR-mediated signaling. Importantly, pharmacological balancing of NMDAR signaling in these mouse models with diametric Cyfip1 dosages rescues behavioral abnormalities. Conclusions CYFIP1 regulates protein translation of NMDAR and associated complex components at synapses to maintain normal synaptic functions and behaviors. Our integrated analyses provide insight into how gene dosage imbalance caused by CNVs may contribute to divergent neuropsychiatric disorders.

Breast neuroendocrine neoplasms (NENs) constitute a rare histologic subtype that includes both neuroendocrine tumors (NETs) and neuroendocrine carcinomas (NECs). In this study, we aimed to gain insight into the clinical and molecular characteristics of NENs of the breast. NEN and paired distant normal fresh tissues and clinicopathological data were obtained from 17 patients with NENs, and clinicopathological data were collected from 755 patients with invasive breast carcinomas of no special type (IBCs-NST). We compared the clinicopathological characteristics of NENs and IBCs-NST and performed whole-exome sequencing (WES) of both NEN and paired normal tissues. Compared with the IBC-NST patients, the NEN patients had a higher mean age, lower clinical stage, and lower pathological nodal (pN) stage (P

Large-scale genomic studies of schizophrenia have identified hundreds of genetic loci conferring risk to the disorder. This progress offers an important route toward defining the biological basis of the condition and potentially developing new treatments. In this review, we discuss insights from recent genome-wide association study, copy number variant, and exome sequencing analyses of schizophrenia, together with functional genomics data from the pre- and postnatal brain, in relation to synaptic development and function. These data provide strong support for the view that synaptic dysfunction within glutamatergic and GABAergic (gamma-aminobutyric acidergic) neurons of the cerebral cortex, hippocampus, and other limbic structures is a central component of schizophrenia pathophysiology. Implicated genes and functional genomic data suggest that disturbances in synaptic connectivity associated with susceptibility to schizophrenia begin in utero but continue throughout development, with some alleles conferring risk to the disorder through direct effects on synaptic function in adulthood. This model implies that novel interventions for schizophrenia could include broad preventive approaches aimed at enhancing synaptic health during development as well as more targeted treatments aimed at correcting synaptic function in affected adults.

BACKGROUND: A number of rare copy number variants (CNVs) have been linked to neurodevelopmental disorders. However, because CNVs encompass many genes, it is often difficult to identify the mechanisms that lead to developmental perturbations.METHODS: We used 15q13.3 microdeletion to propose and validate a novel strategy to predict the impact of CNV genes on brain development that could further guide functional studies. We analyzed single-cell transcriptomics datasets containing cortical interneurons to identify their developmental vulnerability to 15q13.3 microdeletion, which was validated in mouse models.RESULTS: We found that Klf13-but not other 15q13.3 genes-is expressed by precursors and neuroblasts in the medial and caudal ganglionic eminences during development, with a peak of expression at embryonic day (E)13.5 and E18.5, respectively. In contrast, in the adult mouse brain, Klf13 expression is negligible. Using Df(h15q13.3)/+ and Klf13+/- embryos, we observed a precursor subtype-specific impairment in proliferation in the medial ganglionic eminence and caudal ganglionic eminence at E13.5 and E17.5, respectively, corresponding to vulnerability predicted by Klf13 expression patterns. Finally, Klf13+/- mice showed a layer-specific decrease in parvalbumin and somatostatin cortical interneurons accompanied by changes in locomotor and anxiety-related behavior.CONCLUSIONS: We show that the impact of 15q13.3 microdeletion on precursor proliferation is grounded in a reduction in Klf13 expression. The lack of Klf13 in Df(h15q13.3)/+ cortex might be the major reason for perturbed density of cortical interneurons. Thus, the behavioral defects seen in 15q13.3 microdeletion could stem from a developmental perturbation owing to selective vulnerability of cortical interneurons during sensitive stages of their development.

Structural variation (SV) is a large difference (typically >100 bp) in the genomic structure of two genomes and includes both copy number variation and variation that does not change copy number of a genomic region, such as an inversion. Improved reference genomes, combined with widespread genome sequencing using short-read sequencing technology, and increasingly using long-read sequencing, have reignited interest in SV. Recent large-scale studies and functional focused analyses have highlighted the role of SV in human evolution. In this review, we highlight human-specific SVs involved in changes in the brain, population-specific SVs that affect response to the environment, including adaptation to diet and infectious diseases, and summarise the contribution of archaic hominin admixture to present-day human SV.

Multiple myeloma presents with numerous primary genomic lesions that broadly dichotomize cases into hyperdiploidy or IgH translocated. Clinically, these large alterations are assessed by fluorescence in situ hybridization (FISH) for risk stratification at diagnosis. Secondary focal events, including indels and single-nucleotide variants, are also reported; however, their clinical correlates are poorly described, and FISH has insufficient resolution to assess many of them. This study examined the exonic sequences of 26 genes reported to be mutated in >1% of patients with myeloma using a custom panel. These exons were sequenced to approximately 1000 times in a cohort of 76 patients from Atlantic Canada with detailed clinical correlates and in four multiple myeloma cell lines. Across the 76 patients, 255 mutations and 33 focal copy number variations were identified. High-severity mutations and mutations predicted by FATHMM-XF to be pathogenic identified patients with significantly reduced progression-free survival. These mutations were mutually exclusive from the Revised International Staging System high-risk FISH markers and were independent of all biochemical parameters of the Revised International Staging System. Applying our panel to patients classified by FISH to be standard risk successfully reclassified patients into high- and standard-risk groups. Furthermore, three patients in our cohort each had two high-risk markers; two of these patients developed plasma cell leukemia, a rare and severe clinical sequela of multiple myeloma.

Citrin deficiency is one of the most common inborn errors of metabolism in East Asians, which may manifest as neonatal cholestasis, failure to thrive and dyslipidaemia, or recurrent hyperammonaemic encephalopathy. Its molecular diagnosis requires confirmation of the presence of biallelic pathogenic variants in SLC25A13 gene by sequencing, and analysis for a common insertion IVS16ins3kb. However, patients with compatible biochemical features but only one monoallelic pathogenic variant have remained a diagnostic challenge. Here we report the development, validation and application of a multiplex ligation-dependent probe amplification (MLPA) assay using an in-house oligonucleotide probemix and a customised Coffalyer.NET worksheet for detection of exonic copy number variations in SLC25A13. With this MLPA assay, we successfully identified the presence of a heterozygous exonic deletion in SLC25A13 in three of 15 (20%) unrelated individuals with only one monoallelic pathogenic variant detected using conventional methods. Three exonic deletions, two novel involving exon 14 and one reported involving exon 5, were subsequently confirmed with Sanger sequencing. In summary, we developed, evaluated, and demonstrated the clinical utility of an in-house MLPA assay to look for exonic deletions in SLC25A13 in patients with citrin deficiency. With the discovery of novel deletions, MLPA should be considered a test of choice for molecular diagnosis of citrin deficiency when the sequencing result is inconclusive.

Neurodevelopmental disorder with absent language and variable seizures (NEDALVS, OMIM # 618707) is a newly described autosomal dominant condition caused by heterozygous de novo mutation in WASF1 gene. WASF1 is a key component of the WAVE regulatory complex (WRC) required for actin polymerization. So far, only 3 distinct truncating variants clustering at the WCA domain, 3 missense variants localized to the meander region and a copy number variant (CNV) of WASF1 have been identified among 11 NEDALVS cases previously reported.We report a pediatric patient carrying novel de novo heterozygous missense variant (NM_003931.2: c.481T C, p.Trp161Arg) in WASF1 gene. During the first hospitalization at age of 5.5 months, the patient was initially diagnosed with infantile spasms, developmental delay (DD) and microcephaly due to nodding-like epileptic spasms in clusters and hypsarrhythmia on video-electroencephalography, lacking head control and body rollover, and abnormal head circumference 39 cm (-2SD). The genetic diagnosis with a causal WASF1 variant detected by trio exome sequencing indicated the rare NEDALVS.All the reported NEDALVS cases published in the PubMed English literature were reviewed to summarize the genetic and phenotypic spectrum of this novel disorder.We describe the third patient with a recurrently mutated amino acid site at p.Trp161 in WASF1, currently the 12th patient with NEDALVS. This hotspot missense variant and the truncating variants in WASF1 lead to similar phenotypic patterns with core features of severe DD/ID, and seizures, hypotonia, and microcephaly frequently observed. Our finding expands the WASF1 mutation spectrum and confirms the de novo hotspot missense variant at p.Trp161, further supporting the association of the novel NEDALVS with WASF1 gene and the actin regulatory pathway.

Modern genomic sequencing tests often interrogate large numbers of genes. Identification of appropriate reference materials for development, validation studies, and quality assurance of these tests poses a significant challenge for laboratories. It is difficult to develop and maintain expert knowledge to identify all variants that must be validated to ensure analytic and clinical validity. Additionally, it is usually not possible to procure appropriate and characterized genomic DNA reference materials containing the number and scope of variants required. To address these challenges, the Centers for Disease Control and Prevention's Genetic Testing Reference Material Program (GeT-RM) has partnered with the Clinical Genome Resource (ClinGen) to develop a publicly available list of expert curated, clinically important variants. ClinGen Variant Curation Expert Panels nominated 546 variants found in 84 disease-associated genes, including common pathogenic and difficult-to-detect variants. Variant types nominated included 346 single nucleotide variants, 104 deletions, 37 copy number variants, 25 duplications, 18 deletion-insertions, 5 inversions, 4 insertions, 2 complex rearrangements, 3 difficult-to-sequence regions, and 2 fusions. This expert-curated variant list is a resource that provides a foundation for designing comprehensive validation studies and for creating in silico reference materials for clinical genomic test development and validation.

Objective To evaluate the detection rate (DR) by prenatal cell-free DNA test for pathogenic copy number variations (CNVs)＞2 Mb among pregnancies with fetal ultrasound abnormalities. Materials and methods This was a retrospective study on 29 pregnant women with fetuses diagnosed as microdeletion/microduplication syndromes by prenatal chromosome microarray analysis (CMA). Cell-free DNA from the maternal plasma was sequenced on the NextSeq CN500 sequencer. The quality standard of unique map reads in a single sample was greater than 10 M and only gains and losses of more than 2 Mb were reported. Results A total of 24 CNVs were identified by cell-free DNA test among the 21 fetuses with pathogenic CNVs identified by prenatal CMA, including 20 consistent CNVs and 4 inconsistent CNVs. Overall, the DR of cell-free DNA test for pathogenic CNVs ＞2 Mb was 69%. Microdeletions or microduplications at 22q11.2 were the most common CNVs, with a DR of 4/5 (80%) and 3/4 (75%) respectively. Conclusion Cell-free DNA test exhibited a moderate DR for pathogenic CNVs ＞2 Mb among fetuses with ultrasound abnormalities. Cell-free DNA test could provide an opportunity for early screening before the appearance of abnormalities on fetal ultrasound, while further clinical data and cost-effectiveness assessment are needed.

Progressive familial intrahepatic cholestasis type 1 (PFIC1) results from biallelic pathogenic variants in ATP8B1. This study sought second pathogenic variants in ATP8B1 by whole-genome sequencing (WGS) in four unrelated low γ-glutamyl transpeptidase cholestasis patients in whom clinical suspicion of PFIC1 was high and gene-panel or Sanger sequencing had identified only one pathogenic variant in ATP8B1. Sanger sequencing confirmed WGS findings and determined the origin of each variant. Novel nonrecurrent structural variants in three patients (patient 1 to patient 3) were identified in trans: g.55396652_55403080del (6427-bp deletion), g.55335906_55346620dup (10,715-bp duplication), and g.55362063_55364293dup (2231-bp duplication). One synonymous variant in patient 4 was recognized in trans (c.1029GA, p. Thr343Thr) and demonstrated as deleterious. In conclusion, WGS improves genetic diagnostic yield in PFIC1. These findings expand the gene-variant spectrum associated with familiar intrahepatic cholestasis 1 (FIC1) disease and for the first time report tandem duplication in ATP8B1 associated with cholestasis.

Next-generation sequencing (NGS) has proved to be a beneficial approach for genotyping solid tumor specimens and for identifying clinically actionable mutations. However, copy number variations (CNVs), which can be equally important, are often challenging to detect from NGS data. Current bioinformatics methods for CNV detection from NGS often require comparison of tumor/normal pairs and/or the sequencing of whole genome or whole exome. These approaches are currently impractical for routine clinical practice. However, clinical practice does involve repeated use of the same gene panel on a large number of specimens over a long period of time. We take advantage of this repetitiveness and present SILO: a procedure for CNV detection based on NGS on a gene panel. The SILO algorithm analyzes coverage depth of the aligned reads from a sample and predicts CNV by comparing this depth to the average depth seen in a large training set of other samples. Such comparison is robust and can reliably detect copy number gain, although it is found to be unreliable in detecting copy number losses. Successful validation of SILO on NGS data from the Ion Torrent platform with two panels is presented: a small hotspot panel and a larger cancer gene panel.

Integrative analysis of histopathology images and genomic data enables the discovery of potential biomarkers and multimodal association patterns. However, few studies have established effective association models for complex diseases, such as sarcoma, by combining histopathological images with multiple genetic variation data. Here, we present an integrative multiple genomic imaging framework called multi-dimensional constrained joint non-negative matrix factorization (MDJNMF) to identify modules related to lung metastasis of sarcomas based on sample-matched whole-solid image, DNA methylation , and copy number variation features. Three types of feature matrices were projected onto a common feature space, in which heterogeneous variables with large coefficients in the same projected direction form a common module. The correlation between image features and genetic variation features is used as network-regularized constraints to improve the module accuracy. Sparsity and orthogonal constraints are utilized to achieve the modular sparse solution . Multi-level analysis indicates that our method effectively discovers biologically functional modules associated with sarcoma or lung metastasis. The representative module reveals a significant correlation between image features and genetic variation features and excavates potential diagnostic biomarkers. In summary, the proposed method provides new clues for identifying association patterns and biomarkers using multiple types of data sources for other diseases.

Tumors of purported specialized prostatic stromal origin comprise prostatic stromal sarcomas (PSS) and stromal tumors of uncertain malignant potential (STUMP). Prior studies have described their clinicopathologic characteristics, but the molecular features remain incompletely understood. Moreover, these neoplasms are morphologically heterogeneous and the lack of specific adjunctive markers of prostatic stromal lineage make precise definition more difficult, leading some to question whether they represent a specific tumor type. In this study, we used next-generation DNA and RNA sequencing to profile 25 primary prostatic mesenchymal neoplasms of possible specialized prostatic stromal origin, including cases originally diagnosed as PSS (11) and STUMP (14). Morphologically, the series comprised 20 cases with solid architecture (11 PSS and 9 STUMP) and 5 cases with phyllodes-like growth pattern (all STUMP). Combined DNA and RNA sequencing results demonstrated that 19/22 (86%) cases that underwent successful sequencing (either DNA or RNA) harbored pathogenic somatic variants. Except for TP53 alterations (6 cases), ATRX mutations (2 cases), and a few copy number variants (-13q, -14q, -16q and +8/8p), the findings were largely nonrecurrent. Eight gene rearrangements were found, and 4 (NAB2-STAT6, JAZF1-SUZ12, TPM3-NTRK1 and BCOR-MAML3) were useful for reclassification of the cases as specific entities. The present study shows that mesenchymal neoplasms of the prostate are morphologically and molecularly heterogeneous and include neoplasms that harbor genetic aberrations seen in specific mesenchymal tumors arising in other anatomic sites, including soft tissue and the uterus. These data suggest that tumors of purported specialized prostatic stromal origin may perhaps not represent a single diagnostic entity or specific disease group and that alternative diagnoses should be carefully considered.

Summary Nuclear protein in testis (NUT) carcinoma (NC) is a rare and aggressive neoplasm associated with a rearrangement of the NUT gene on chromosome 15q14. To date, genomic alterations of NCs, especially those in the lung, are poorly understood. In this study, immunohistochemistry staining, fluorescence in situ hybridization, and two next-generation sequencing (NGS) panels of 56 and 701 genes were used to explore the clinical, pathological, and genetic profiling of pulmonary NCs. Six pulmonary NC cases were confirmed, with a mean age of 41 years (range: 22–69 years) and a median survival time of 6.5 months (range: 2–19 months). Morphologically, typical abrupt keratinization was observed in four of six cases (67%), and two patients presented a mixed pattern of classical squamous component and micropapillary adenocarcinoma morphology. We also identified a case with NUT gene amplification instead of rearrangement. Furthermore, NGS analysis demonstrated the following fusions: BRD4-NUTM1 (2/4 cases) and NSD3-NUTM1 (2/4 cases), and the analysis highlighted 53 gene mutations, including 50 (94.3%, 50/53) single-nucleotide variations (SNVs) and three (5.7%, 3/53) long insertions/deletions. SNVs of MUC16 were the most common and occurred in three cases (75%). Moreover, SNVs of EPHA8, FANCA, TRIO, and USP6 were detected in two of four cases (50%). These 53 mutated genes were involved in 13 functional pathways based on enrichment analysis, especially in the PI3K-Akt signaling pathway. Finally, none of the cases showed obvious copy number variations and had low tumor mutational burden and stable microsatellite sites.

Schizophrenia is a complex brain disorder with genetic and environmental factors contributing to its etiology. Complement C4 genes are schizophrenia susceptibility loci and are activated in response to infections and gut microbiome imbalances. We hypothesize that C4 genetic susceptibility predisposes individuals to neuropathological effects from pathogen exposures or a microbiome in dysbiosis. In 214 individuals with schizophrenia and 123 non-psychiatric controls, we examined C4 gene copy number and haplotype groups for associations with schizophrenia and microbial plasma biomarkers. C4A copy number and haplotypes containing HERV-K insertions (C4A-long; C4AL-C4AL) conferred elevated odds ratios for schizophrenia diagnoses (OR 1.58–2.56, p

Copy number variation (CNV) is a major type of chromosomal structural variation that play important roles in many diseases including cancers. Due to genome instability, a large number of CNV events can be detected in diseases such as cancer. Therefore, it is important to identify the functionally important CNVs in diseases, which currently still poses a challenge in genomics. One of the critical steps to solve the problem is to define the influence of CNV. In this paper, we provide a topology potential based method, TPQCI, to quantify this kind of influence by integrating statistics, gene regulatory associations, and biological function information. We used this metric to detect functionally enriched genes on genomic segments with CNV in breast cancer and multiple myeloma and discovered biological functions influenced by CNV. Our results demonstrate that, by using our proposed TPQCI metric, we can detect disease-specific genes that are influenced by CNVs. Source codes of TPQCI are provided in Github (https://github.com/usos/TPQCI).

PI3K-AKT pathway mutations initiate a kinase cascade that characterizes endometrial cancer (EC). As kinases seldom cause oncogenic transformation without dysregulation of antagonistic phosphatases, pivotal interactions governing this pathway were explored and correlated with clinical outcomes.After exclusion of patients with POLE mutations from The Cancer Genome Atlas EC cohort with endometrioid or serous EC, the study population was 209 patients with DNA sequencing, quantitative gene-specific RNA expression, copy number variation (CNV), and surveillance data available. Extracted data were annotated and integrated.A PIK3CA, PTEN, or PIK3R1 mutant (-mu) was present in 83% of patients; 57% harbored more than 1 mutation without adversely impacting progression-free survival (PFS) (P = .10). PIK3CA CNV of at least 1.1 (CNV high [-H]) was detected in 26% and linked to TP53-mu and CIP2A expression (P.001) but was not associated with PFS (P = .24). PIK3CA expression was significantly different between those with CIP2A-H and CIP2A low (-L) expression (the endogenous inhibitor of protein phosphatase 2A [PP2A]), when stratified by PIK3CA mutational status or by PIK3CA CNV-H and CNV-L (all P.01). CIP2A-H or PPP2R1A-mu mitigates PP2A kinase dephosphorylation, and FBXW7-mu nullifies E3 ubiquitin ligase (E3UL) oncoprotein degradation. CIP2A-H and PPP2R1A-mu (PP2A impairment) and FBXW7-mu (E3UL impairment) were associated with compromised PFS (P.001) and were prognostically discriminatory for PIK3CA-mu and PIK3CA CNV-H tumors (P.001). Among documented recurrences, 84% were associated with impaired PP2A (75%) and/or E3UL (20%).PP2A and E3UL deficiencies are seminal biological drivers in EC independent of PIK3CA-mu, PTEN-mu, and PIK3R1-mu and PIK3CA CNV.

The promise of using induced pluripotent stem cells (iPSCs) for cellular therapies has been hampered by the lack of easily isolatable and well characterized source cells whose genomes have undergone minimal changes during their processing. Blood-derived late-outgrowth endothelial progenitor cells (EPCs) are used for disease modeling and have potential therapeutic uses including cell transplantation and the translation of induced pluripotent stem cell (iPSC) derivatives. However, the current isolation of EPCs has been inconsistent and requires at least 40-80 mL of blood, limiting their wider use. In addition, previous EPC reprogramming methods precluded the translation of EPC-derived iPSCs to the clinic. Here a series of clinically-compatible advances in the isolation and reprogramming of EPCs is presented, including a reduction of blood sampling volumes to 10 mL and use of highly efficient RNA-based reprogramming methods together with autologous human serum, resulting in clinically relevant iPSCs carrying minimal copy number variations (CNVs) compared to their parent line.

Purpose Pregnant women have unprecedented choices for prenatal screening and testing. Cell-free DNA (cfDNA) offers the option to screen for aneuploidy of all chromosomes and genome-wide copy-number variants (CNVs), expanding screening beyond the common trisomies ("traditional" cfDNA). We sought to review the utilization trends and clinical performance characteristics of a commercially available genome-wide cfDNA test, with a subset having available diagnostic testing outcomes. Methods Retrospective analysis of 55,517 samples submitted for genome-wide cfDNA screening at a commercial laboratory, assessing indications, demographics, results, and performance. The cohort was broken into three "testing years"' to compare trends. Results Indications shifted over time, with a decrease in referrals for ultrasound findings (22.0% to 12.0%) and an increase in no known high-risk indication (3.0% to 16.6%). Of the positive results, 25% would be missed with traditional cfDNA screening. High sensitivity and specificity were observed with a positive predictive value (PPV) of 72.6% for genome-wide CNVs and 22.4% for rare autosomal trisomies (RATs). Conclusion A broader patient population is utilizing genome-wide cfDNA, yet positivity rates and the contribution of genome-wide events have remained stable at approximately 5% and 25%, respectively. Test performance in a real-world clinical population shows high PPVs in those CNVs tested, with diagnostic outcomes in over 40% of positive cases.

Single-cell genomics provides substantial resources for dissecting cellular heterogeneity and cancer evolution. Unfortunately, classical DNA amplification-based methods have low throughput and introduce coverage bias during sample preamplification. We developed a single-cell DNA library preparation method without preamplification in nanolitre scale (scDPN) to address these issues. The method achieved a throughput of up to 1800 cells per run for copy number variation (CNV) detection. Also, our approach demonstrated a lower level of amplification bias and noise than the multiple displacement amplification (MDA) method and showed high sensitivity and accuracy for cell line and tumour tissue evaluation. We used this approach to profile the tumour clones in paired primary and relapsed tumour samples of hepatocellular carcinoma (HCC). We identified three clonal subpopulations with a multitude of aneuploid alterations across the genome. Furthermore, we observed that a minor clone of the primary tumour containing additional alterations in chromosomes 1q, 10q, and 14q developed into the dominant clone in the recurrent tumour, indicating clonal selection during recurrence in HCC. Overall, this approach provides a comprehensive and scalable solution to understand genome heterogeneity and evolution.

Copy number variation (CNV) at 7q11.23 causes distinct disorders with both contrasting and overlapping phenotypic features of some but not all of the genes encompassed by the CNV. The spectrum of cognitive disabilities, psychopathology and altered behaviours associated with 7q11.23 CNV provides a tantalizing window of opportunity to better understand the molecular bases for complex human cognitive function and social behaviour. Study of individuals with atypical CNVs has narrowed the field of candidate genes, and the generation of mouse models has allowed further insight into their functions. Recent research has used high-throughput genomics techniques to interrogate the transcriptome and methylome, and initial strategies to correct gene transcription levels, pathophysiology and cognitive and behavioural phenotypes show promise.

Genomic disorders result from rearrangement of the human genome. Most genomic disorders are caused by copy number variants (CNV), deletions or duplications of several hundred kilobases. Many CNV loci are associated with autism, schizophrenia, and most commonly, intellectual disability (ID). However, there is little comparison of cognitive ability measures across these CNV disorders. This study aims to understand whether existing data can be leveraged for a cross-comparison of cognitive ability among multiple CNV. We found there is a lack of harmonization among assessment instruments and little standardization for reporting summary data across studies. Despite these limitations, we identified a differential impact of CNV loci on cognitive ability. Our data suggest that future cross-comparisons of CNV disorders will reveal meaningful differences across the phenotypic spectrum, especially if standardized phenotypic assessment is achieved.

Among medical disciplines, diagnosis in psychiatry depends highly upon descriptive signs and symptoms, rather than biomarkers. Clear descriptions of specific genetic etiologies have been lacking; genomic technologies, however, are rapidly changing that landscape. Notably, chromosomal microarrays-which detect gene copy number variants (CNVs)-are a recommended standard of care for neurodevelopmental disorders. As a result, an increasing number of patients now receive a clinical diagnosis based on the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) and an identified genetic etiological variant. However, psychiatric and genetic diagnoses are frequently communicated and managed as two disconnected diagnostic parameters. Here, we advocate for a transition model, allowing the integration of genetic etiological information-starting with diagnostically proven CNVs-within the DSM-5 classification framework.

Background Identification of genomic alterations present in cancer patients may aid in cancer diagnosis, prognosis and therapeutic target discovery. In this study, we aimed to identify clinically actionable variants present in stage IV breast cancer (BC) samples. Materials and Methods DNA was extracted from formalin-fixed paraffin-embedded samples of BC (n = 41). DNA was sequenced using MammaSeq, a BC-specific next-generation sequencing panel targeting 79 genes and 1369 mutations. Ion Torrent Suite 4.0 was used to make variant calls on the raw data, and the resulting single nucleotide variants were annotated using the CRAVAT toolkit. Single nucleotide variations (SNVs) were filtered to remove common polymorphisms and germline variants. CNVkit was employed to identify copy number variations (CNVs). The Precision Medicine Knowledgebase (PMKB) and OncoKB Precision Oncology Database were used to associate clinical significance with the identified variants. Results A total of 41 samples from Turkish patients with BC were sequenced (read depth of 94-13,340; median of 1529). These patients were diagnosed with various BC subtypes including invasive ductal carcinoma, invasive lobular carcinoma, apocrine BC, and micropapillary BC. In total, 59 different alterations (49 SNVs and 10 CNVs) were identified. From these, 8 alterations (3 CNVs – ERBB2, FGFR1, and AR copy number gains and 5 SNVs – IDH1.R132H, TP53.E204∗, PI3KCA.E545K, PI3KCA.H1047R, and PI3KCA.R88Q) were identified to have some clinical significance by PMKB and OncoKB. Moreover, the top 5 genes with the most SNVs included PIK3CA, TP53, MAP3K1, ATM, and NCOR1. Additionally, copy number gains and losses were found in ERBB2, GRB7, IGFR1, AR, FGFR1, MYC, and IKBKB, and BRCA2, RUNX1, and RB1, respectively. Conclusion We identified 59 unique alterations in 38 genes in 41 stage IV BC tissue samples using MammaSeqTM. Eight of these alterations were found to have some clinical significance by OncoKB and PKMB. This study highlights the potential use of cancer specific next-generation sequencing panels in clinic to get better insight into the patient-specific genomic alterations.

Neurexins are central to trans-synaptic cell adhesion and signaling during synapse specification and maintenance. The past two decades of human genetics research have identified structural variations in the neurexin gene family, in particular NRXN1 copy number variants (CNVs), implicated in multiple neuropsychiatric and developmental disorders. The heterogeneity and reduced penetrance of NRXN1 deletions, in addition to the pleiotropic, circuit-specific functions of NRXN1, present substantial obstacles to understanding how compromised NRXN1 function predisposes individuals to neuropsychiatric disorders. Here, we provide an updated review of NRXN1 genetics in disease, followed by recently published work using both human induced pluripotent stem cell (iPSC) derived systems and animal models to understand the mechanisms of disease pathophysiology. Finally, we suggest our outlook on how the field should progress to improve our understanding of neurexin mediated disease pathogenesis. We believe that understanding how structural genetic variants in NRXN1 contribute to disease pathophysiology requires parallel approaches in iPSC and mouse model systems, each leveraging their unique strengths — analysis of genetic interactions and background effects in iPSCs and neural circuit and behavioral analysis in mice.

Human genetics is providing much needed clues to mechanisms underlying neuropsychiatric disorders. Highly penetrant copy number variants (CNVs) were among the first genetic variants confidently associated with schizophrenia and autism spectrum disorders (ASDs). Despite their structural complexity, the high penetrance of CNVs associated with neuropsychiatric disorders suggested utility for construction of cellular and animal models. Human cellular models that carry disease associated alleles have the advantage of human genetic backgrounds against which to study the effects of CNVs. However, investigation of the effects of disease-associated alleles on the structure and function of living brains requires genome engineering of model organisms or introduction of genetic material into their brains by viral vectors. Here I focus on the translational utility of transgenic mice that carry models of human neuropsychiatric CNVs, while recognizing their limitations as veridical models of complex human brain disorders. In order to improve translational utility and avoid the intellectual cul-de-sacs that often bedevil interpretation of neuropsychiatric disease models, I conclude with a 'draft' proposal to replace current concepts of construct and face validity with more nuanced and contextually relevant judgments.

International audience; Copy Number Variants (CNVs) are associated with elevated rates of neuropsychiatric disorders. A 'genetics-first' approach, involving the CNV effects on the brain, irrespective of clinical symptomatology, allows investigation of mechanisms underlying neuropsychiatric disorders in the general population. Recent years have seen an increasing number of larger multisite neuroimaging studies investigating the effect of CNVs on structural and functional brain endophenotypes. Alterations overlap with those found in idiopathic psychiatric conditions but effect sizes are twofold to fivefold larger. Here we review new CNV-associated structural and functional brain alterations and outline the future of neuroimaging genomics research, with particular emphasis on developing new resources for the study of high-risk CNVs and rare genomic variants.

Copy number variants (CNVs) have been implicated in neuropsychiatric disorders, with rare-inherited and de novo CNVs (dnCNVs) having large effects on disease liability. Recent studies started exploring a class of dnCNVs that occur post-zygotically, and are therefore present in some but not all cells of the body. Analogous to conditional mutations in animal models, the presence of risk mutations in a fraction of cells has the potential to enlighten how damaging mutations affect cell-type/cell-circuit specific pathologies leading to neuropsychiatric manifestations. Although mosaic CNVs appear to contribute to a modest fraction of risk (0.3–0.5%), expanding our insights about them with more sensitive experimental and statistical methods, has the potential to help clarify mechanisms of neuropsychiatric disease.

Virtually all genome sequencing efforts in national biobanks, complex and Mendelian disease programs, and medical genetic initiatives are reliant upon short-read whole-genome sequencing (srWGS), which presents challenges for the detection of structural variants (SVs) relative to emerging long-read WGS (lrWGS) technologies. Given this ubiquity of srWGS in large-scale genomics initiatives, we sought to establish expectations for routine SV detection from this data type by comparison with lrWGS assembly, as well as to quantify the genomic properties and added value of SVs uniquely accessible to each technology. Analyses from the Human Genome Structural Variation Consortium (HGSVC) of three families captured ~11,000 SVs per genome from srWGS and ~25,000 SVs per genome from lrWGS assembly. Detection power and precision for SV discovery varied dramatically by genomic context and variant class: 9.7% of the current GRCh38 reference is defined by segmental duplication (SD) and simple repeat (SR), yet 91.4% of deletions that were specifically discovered by lrWGS localized to these regions. Across the remaining 90.3% of reference sequence, we observed extremely high (93.8%) concordance between technologies for deletions in these datasets. In contrast, lrWGS was superior for detection of insertions across all genomic contexts. Given that non-SD/SR sequences encompass 95.9% of currently annotated disease-associated exons, improved sensitivity from lrWGS to discover novel pathogenic deletions in these currently interpretable genomic regions is likely to be incremental. However, these analyses highlight the considerable added value of assembly-based lrWGS to create new catalogs of insertions and transposable elements, as well as disease-associated repeat expansions in genomic sequences that were previously recalcitrant to routine assessment.

Cytochrome P450 2D6 (CYP2D6) copy number (CN) variation affects the metabolism of numerous prescribed drugs. Sequence variation within primer or probe target regions of hydrolysis probe CN assays can generate false-positive calls for CN loss. Furthermore, CYP2D6–CYP2D7 hybrids and gene conversions can cause difficult to interpret discordant CN calls. The identification of haplotypes with CN variations and structural arrangements is important to predict phenotype accurately. During clinical testing with hydrolysis probe assays targeting three CYP2D6 regions (intron 2, intron 6, and exon 9), samples with haplotypes causing inconsistent CN calls were identified. To resolve these cases, next-generation sequencing and allele-specific Sanger sequencing was performed. Sequence analysis of 16 samples, all but one from subjects of African descent, identified six novel suballeles containing single-nucleotide polymorphisms, which cause false-positive calls for CN loss in introns 2 and 6. Five samples with an exon 9 CN loss contained CYP2D6/CYP2D7 hybrids (∗13 or ∗36) and one sample was found to have a novel haplotype, CYP2D6∗141. Interestingly, CYP2D6∗141 contains a CYP2D7-derived exon 9 conversion and core single-nucleotide polymorphisms that are otherwise found in CYP2D6∗17 and ∗27. Although these variants are rare, they can cause inconsistent CN calls that typically are reported as no calls or indeterminant, and thus may deprive patients, particularly those of African descent, from taking full benefit of pharmacogenetic testing.

Summary Each human genome includes de novo mutations that arose during gametogenesis. While these germline mutations represent a fundamental source of new genetic diversity, they can also create deleterious alleles that impact fitness. Whereas the rate and patterns of point mutations in the human germline are now well understood, far less is known about the frequency and features that impact de novo structural variants (dnSVs). We report a family-based study of germline mutations among 9,599 human genomes from 33 multigenerational CEPH-Utah families and 2,384 families from the Simons Foundation Autism Research Initiative. We find that de novo structural mutations detected by alignment-based, short-read WGS occur at an overall rate of at least 0.160 events per genome in unaffected individuals, and we observe a significantly higher rate (0.206 per genome) in ASD-affected individuals. In both probands and unaffected samples, nearly 73% of de novo structural mutations arose in paternal gametes, and we predict most de novo structural mutations to be caused by mutational mechanisms that do not require sequence homology. After multiple testing correction, we did not observe a statistically significant correlation between parental age and the rate of de novo structural variation in offspring. These results highlight that a spectrum of mutational mechanisms contribute to germline structural mutations and that these mechanisms most likely have markedly different rates and selective pressures than those leading to point mutations.

Objective Detecting traces of ancient DNA of Vibrio cholerae to provide genetic information associated with the fifth cholera pandemic. Materials Sediment samples from the sacral foramina of four individuals were analyzed, recovered from a mass grave near an institution dedicated exclusively to the isolation and treatment of citizens infected with cholera in the late 19th century in the city of Cordoba, Argentina. Methods Paleogenetic techniques (ancient DNA extraction, PCR amplification, and Sanger sequencing) were applied. Specific primers for Vibrio cholerae (VCR, ctxA, ctxB, and tcpA) were designed. Results By amplifying and sequencing the Vibrio cholerae repeats fragment, the infection in at least one individual was confirmed. Conclusions The synthesis of the paleogenetic results with the archaeological and historical evidence strongly supports that at least one individual from the mass grave in Cordoba, Argentina, was a victim of the fifth cholera pandemic. Significance Confirming the presence of the disease through multiple lines of evidence, including genetic, archaeological, and historical analyses, strengthens and affirms our understanding of the presence, effects, and potential evolutionary paths of the disease in the past. Limitations Vibrio cholerae repeats were sequenced in one individual, while the remaining genes could not be amplified, which is likely related to gene copy number. Suggestions for future research Paleogenetic examination of ancient samples from different locations will broaden our understanding of the origin, evolution, and past dissemination of Vibrio cholerae epidemic strains.

Background The 15q13.3 microdeletion is associated with several neuropsychiatric disorders, including autism and schizophrenia. Previous association and functional studies have investigated the potential role of several genes within the deletion in neuronal dysfunction, but the molecular effects of the deletion as a whole remain largely unknown. Methods Induced pluripotent stem cells, from 3 patients with the 15q13.3 microdeletion and 3 control subjects, were generated and converted into induced neurons. We analyzed the effects of the 15q13.3 microdeletion on genome-wide gene expression, DNA methylation, chromatin accessibility, and sensitivity to cisplatin-induced DNA damage. Furthermore, we measured gene expression changes in induced neurons with CRISPR (clustered regularly interspaced short palindromic repeats) knockouts of individual 15q13.3 microdeletion genes. Results In both induced pluripotent stem cells and induced neurons, gene copy number change within the 15q13.3 microdeletion was accompanied by significantly decreased gene expression and no compensatory changes in DNA methylation or chromatin accessibility, supporting the model that haploinsufficiency of genes within the deleted region drives the disorder. Furthermore, we observed global effects of the microdeletion on the transcriptome and epigenome, with disruptions in several neuropsychiatric disorder–associated pathways and gene families, including Wnt signaling, ribosome function, DNA binding, and clustered protocadherins. Individual gene knockouts mirrored many of the observed changes in an overlapping fashion between knockouts. Conclusions Our multiomics analysis of the 15q13.3 microdeletion revealed downstream effects in pathways previously associated with neuropsychiatric disorders and indications of interactions between genes within the deletion. This molecular systems analysis can be applied to other chromosomal aberrations to further our etiological understanding of neuropsychiatric disorders.

Morquio B disease is an attenuated phenotype within the spectrum of beta galactosidase (GLB1) deficiencies. It is characterised by dysostosis multiplex, ligament laxity, mildly coarse facies and heart valve defects due to keratan sulphate accumulation, predominantly in the cartilage. Morquio B patients have normal neurological development, setting them apart from those with the more severe GM1 gangliosidosis. Morquio B disease, with an incidence of 1:250.000 to 1:1.000.000 live births, is very rare. Here we report the clinical-biochemical data of nine patients. High amounts of keratan sulfate were detected using LC-MS/MS in the patients' urinary samples, while electrophoresis, the standard procedure of qualitative glycosaminoglycans analysis, failed to identify this metabolite in any of the patients' samples. We performed molecular analyses at gene, gene expression and protein expression levels, for both isoforms of the GLB1 gene, lysosomal GLB1, and the cell-surface expressed Elastin Binding Protein. We characterised three novel GLB1 mutations [c.75 + 2 T > G, c.575A > G (p.Tyr192Cys) and c.2030 T > G (p.Val677Gly)] identified in three heterozygous patients. We also set up a copy number variation assay by quantitative PCR to evaluate the presence of deletions/ insertions in the GLB1 gene. We propose a diagnostic plan, setting out the specific clinical- biochemical and molecular features of Morquio B, in order to avoid misdiagnoses and improve patients' management.

Objectives Oxidative stress has been hypothesized as a central component of both placental and endothelial dysfunction, leading to PE. This oxidative stress leading to mitochondrial dysfunction may be due to variations in mtDNA copy numbers as an adaptive response. In the present study we aimed to analyse mtDNA copy numbers in the placenta obtained after delivery from the women with PE as compared to the controls. Study design It was a prospective case control study. A total of 32 placental samples were analyzed (Cases: 17; Controls: 15). Samples were collected ex vivo, after childbirth. MtDNA content was determined useing real-time quantitative PCR qRT-PCR) using TaqMan probes designed for two genes: MT-ND1 and a mitochondrial gene encoding for the NADH dehydrogenase 1 protein. Results We found that the median (IQR) mtDNA copy number was higher in PE cases 24.32 (9.260–33.51) as compared with controls 20.32 (13.33–26.22). On subgroup analysis, the median (IQR) mtDNA copy number was higher in early onset PE 28.06 (20.80–36.87) as compared to late onset PE 9.215 (4.150–56.45) as well as the controls 20.32 (13.33–26.22). Conclusion Our findings support a higher mtDNA copy number in early onset PE as compared to late onset PE and control population. Although, mtDNA may only be increased in very severe cases of early onset preeclampsia. Future research may be directed to ascertain if mtDNA copy numbers can be a novel biomarker to predict or prognosticate early onset preeclampsia.

Objective To present the experience on prenatal features of 17q12 microdeletion and microduplication syndromes. Materials and methods Prenatal chromosomal microarray analysis (CMA) were conducted between January 2015 and December 2018 at a single Chinese tertiary medical centre. Information of cases identified with 17q12 microdeletion or microduplication syndromes were retrospectively collected. Foetal ultrasonographic findings were reviewed, and other information about the gestation week at diagnosis, inheritance and pregnancy outcomes were also included. Results Ten pregnancies with 17q12 microdeletion and 4 with 17q12 microduplication were identified. The copy number variation (CNV) sizes were 1.39–1.94 Mb in the deleted cases and 1.42–1.48 Mb in the duplicated cases, respectively. All the duplicated and deleted regions included HNF1B and LHX1 genes. Most individuals with 17q12 deletion presented kidney anomalies (9/10), with renal hyperechogenicity being the most common finding (7/10). Fetuses with 17q12 duplication presented a wide phenotypic spectrum, including “double bubble” sign, structural anomalies of the heart and growth anomalies. Conclusions Our experience further demonstrated the high correlation between 17q12 microdeletion and renal anomalies especially hyperechogenic kidneys. Structural anomalies of the heart were newly identified phenotypes of 17q12 duplication during prenatal period. Besides, growth anomalies and duodenal atresia might be associated with the duplication.

Objectives Copy-number variations (CNVs) are large-scale deletions or duplications of DNA that have required specialized detection methods, such as microarray-based genomic hybridization or multiplex ligation probe amplification. However, recent advances in bioinformatics have made it possible to detect CNVs from next-generation DNA sequencing (NGS) data. Maturity-onset diabetes of the young (MODY) 5 is a subtype of autosomal-dominant diabetes that is often caused by heterozygous deletions involving the HNF1B gene on chromosome 17q12. We evaluated the utility of bioinformatic processing of raw NGS data to detect chromosome 17q12 deletions in MODY5 patients. Methods NGS data from 57 patients clinically suspected to have MODY but who were negative for pathogenic mutations using a targeted panel were re-examined using a CNV calling tool (CNV Caller, VarSeq version 1.4.3). Potential CNVs for MODY5 were then confirmed using whole-exome sequencing, cytogenetic analysis and breakpoint analysis when possible. Results Whole-gene deletions in HNF1B, ranging from 1.46 to 1.85 million basepairs in size, were detected in 3 individuals with features of MODY5. These were confirmed by independent methods to be part of a more extensive 17q12 deletion syndrome. Two additional patients carrying a 17q12 deletion were subsequently diagnosed using this method. Conclusions Large-scale deletions are the most common cause of MODY5 and can be detected directly from NGS data, without the need for additional methods.

Background and purpose Positive epidermal growth factor receptor (EGFR) immunoreactivity in glioblastoma multiforme (GBM) often predicts poor radiation response. Meanwhile, all attempts to target EGFR pharmaceutically have been unsuccessful, mainly due to molecular heterogeneity of EGFR expression in GBM. A molecular biology-based and efficient way to access cellular protein levels of EGFR is urgently needed. EGFR, together with HIF-1α and Cyclin B1, is degraded via cullin2-RING E3 ligase (CRL2). It is worthwhile to investigate the possible involvement of CRL2 on GBM survival and radiosensitivity. Materials and methods Clinicopathological features, radiographic images, survival data, RNA-Seq, copy number variations (CNVs), and other genetic changes were studied on over 3800 glioma and GBM cases, which are derived from 5 independent cohorts. These datasets include the Chinese Glioma Genome Atlas, The Cancer Genome Atlas, Ivy Glioblastoma Atlas Project, Clinical Proteomic Tumor Analysis Consortium, and the 2008 Parson’s GBM dataset. Results Expression of CUL2, which encodes the scaffold protein cullin2 in the CRL2 E3 ligase, can predict GBM progression and survival rate. Cullin2 protein levels are inversely related to those of HIF-1α, VEGF-A, Cyclin B1, and EGFR. Elevated CUL2 expression predicts increased radiosensitivity and dampened signal intensities in perfusion imaging. CUL2 expression are regulated via CNVs, which are inheritable structural DNA variations. Conclusion CUL2 expression levels and CNVs can be integrated as potential biomarkers in facilitating GBM and prognosis and radiosensitivity profiling.

Copy number variation (CNV) represents a major source of genetic variation, which may have potentially large effects, including alternating gene regulation and dosage, as well as contributing to gene expression and risk for normal phenotypic variability. We carried out a comprehensive analysis of CNV based on whole genome sequencing in Chinese Simmental beef cattle. Totally, we found 9313 deletion and 234 duplication events, covering 147.5 Mb autosomal regions. Within them, 257 deletion events of high frequency overlapped with 193 known RefGenes. Among these genes, we observed several genes were related to economically important traits, like residual feed intake, immune responding, pregnancy rate and muscle differentiation. Using a locus-based analysis, we identified 11 deletions and 1 duplication, which were significantly associated with three traits including carcass weight, tenderloin and longissimus muscle area. Our sequencing-based study provided important insights into investigating the association of CNVs with important traits in beef cattle.

Embryonic chromosomal abnormalities are the major cause of miscarriage. An accurate, rapid, and cheap method of chromosome analysis in miscarriage is warranted in clinical practice. Thus, a high-throughput ligation-dependent probe amplification (HLPA)-based method of detecting aneuploidies and copy number variations in miscarriage was developed. A total of 1060 cases of miscarriage were assessed. Each specimen was subjected to quantitative fluorescence (QF)-PCR/HLPA and chromosomal microarray analysis (CMA) in parallel. All 1060 samples were successfully analyzed using both methods; of these samples, 1.7% (18/1060) were identified as having significant maternal cell contamination. Among the remaining 1042 cases without significant maternal cell contamination, QF-PCR/HLPA reached a diagnostic yield of 59.6% (621/1042), which is comparable to the yield of 60.3% (628/1042) with CMA. Compared with CMA results, the sensitivity and specificity of QF-PCR/HLPA in the identification of total pathogenic chromosomal abnormalities were 98.9% and 100%, respectively. Furthermore, the overall prevalence of chromosomal abnormalities in cases of spontaneous abortion was not significantly different from that in cases of recurrent miscarriage (61.3% versus 58.5%). In summary, QF-PCR/HLPA rapidly and accurately identified chromosomal abnormalities at a comparable performance and lower cost as compared with CMA. Combining simplicity and accuracy with cost-effectiveness, QF-PCR/HLPA may serve as a promising approach to routine genetic testing in miscarriage in clinical practice.

Spinal muscular atrophy (SMA) is an autosomal recessive disorder predominately caused by bi-allelic loss of the SMN1 gene. Increased copies of SMN2, a low functioning nearly identical paralog, are associated with a less severe phenotype. SMA was recently recommended for inclusion in newborn screening. Clinical laboratories must accurately measure SMN1 and SMN2 copy number to identify SMA patients and carriers, and to identify individuals likely to benefit from therapeutic interventions. Having publicly available and appropriately characterized reference materials with various combinations of SMN1 and SMN2 copy number variants is critical to assure accurate SMA clinical testing. To address this need, the CDC-based Genetic Testing Reference Materials Coordination Program, in collaboration with members of the genetic testing community and the Coriell Institute for Medical Research, has characterized 15 SMA reference materials derived from publicly available cell lines. DNA samples were distributed to four volunteer testing laboratories for genotyping using three different methods. The characterized samples had zero to four copies of SMN1 and zero to five copies SMN2. The samples also contained clinically important allele combinations (eg, zero copies SMN1, three copies SMN2), and several had markers indicative of an SMA carrier. These and other reference materials characterized by the Genetic Testing Reference Materials Coordination Program are available from the Coriell Institute and are proposed to support the quality of clinical laboratory testing.

Copy-number variant (CNV) analysis is increasingly performed in genetic diagnostics. We leveraged recent gene curation efforts and technical standards for interpretation and reporting of CNVs to characterize clinically relevant CNVs in patients with inherited heart disease and sudden cardiac death. Exome sequencing data were analyzed for CNVs using eXome-Hidden Markov Model tool in 48 established disease genes. CNV breakpoint junctions were characterized. CNVs were classified using the American College of Medical Genetics and Genomics technical standards. We identified eight CNVs in 690 unrelated probands (1.2%). Characterization of breakpoint junctions revealed nonhomologous end joining was responsible for four deletions, whereas one duplication was caused by nonallelic homologous recombination between duplicated sequences in MYH6 and MYH7. Identifying the precise breakpoint junctions determined the genomic involvement and proved useful for interpreting the clinical relevance of CNVs. Three large deletions involving TTN, MYBPC3, and KCNH2 were classified as pathogenic in three patients. Haplotype analysis of a deletion in ACTN2, found in two families, suggests the deletion was caused by an ancestral event. CNVs infrequently cause inherited heart diseases and should be investigated when standard genetic testing does not reveal a genetic diagnosis.

PURPOSE Copy-number variants (CNVs) of uncertain clinical significance are routinely reported in a clinical setting only when exceeding predetermined reporting thresholds, typically based on CNV size. Given that very few genes are associated with triplosensitive phenotypes, it is not surprising that many interstitial duplications

Chromosomal microarray testing is indicated for patients with diagnoses including unexplained developmental delay or intellectual disability, autism spectrum disorders, and multiple congenital anomalies. The short multiply aggregated sequence homologies (SMASH) genomic assay is a novel next-generation sequencing technology that performs copy number analysis at resolution similar to high-coverage whole genome sequencing but requires far less capacity. We benchmarked the performance of SMASH on a panel of genomic DNAs containing known copy number variants (CNVs). SMASH was able to detect pathogenic copy number variants of ≥10 kb in 77 of 77 samples. No pathogenic events were seen in 32 of 32 controls, indicating 100% sensitivity and specificity for detecting pathogenic CNVs >10 kb. Repeatability (interassay precision) and reproducibility (intra-assay precision) were assessed with 13 samples and showed perfect concordance. We also established that SMASH had a limit of detection of 20% for detection of large mosaic CNVs. Finally, we analyzed seven blinded specimens by SMASH analysis and successfully identified all pathogenic events. These results establish the efficacy of the SMASH genomic assay as a clinical test for the detection of pathogenic copy number variants at a resolution comparable to chromosomal microarray analysis.

Soybean cyst nematode (SCN, Heterodera glycines Ichinohe) is the most economically damaging disease of soybean worldwide, and breeding host plant resistance is the most feasible option for SCN management. In this review, we summarise the progress made so far in identifying nematode-resistance genes, the currently available sources of resistance, possible mechanisms of SCN resistance and strategies for soybean breeding. To date, only two sources of SCN resistance have been widely used, from the accessions PI 88788 and Peking, which has resulted in a shift in SCN resistance and created a narrow genetic base for SCN resistance. These resistant germplasms for SCN are classified into two types according to their copy number variation in a 31-kb genomic region: PI 88788-type resistance requires high copy numbers of a rhg1 resistance allele (rhg1-b) and Peking-type resistance requires both low copy numbers of a different rhg1 resistance allele (rhg1-a) and a resistant allele at another locus, Rhg4. Resistance related to rhg1 primarily involves impairment of vesicle trafficking through disruption of soluble NSF-attachment protein receptor (SNARE) complexes. By contrast, resistance via Rhg4 involves disturbance of folate homeostasis at SCN feeding sites due to alteration of the enzymatic activity of serine hydroxymethyltransferase (SHMT). Other potential mechanisms, including plant defences mediated by salicylic acid (SA) and jasmonic acid (JA) signalling modulation, have also been suggested for SCN resistance. Indeed, genome-wide association studies (GWAS) have identified other candidate SCN resistance genes, such as GmSNAP11. Although gene functional analysis in a transient expression system could increase the efficiency of candidate gene identification, information on novel genes and mechanisms for SCN resistance remains limited. Any beneficial candidate genes identified might, when fully exploited, be valuable for improving the efficiency of marker-assisted breeding and dissecting the molecular mechanisms underlying SCN resistance.

Developmental delay/intellectual disability (DD/ID) is a complex and phenotypically heterogeneous neurodevelopmental disorder characterized by significant deficits in cognitive and adaptive skills, debuting during the developmental period. In this study, we evaluated the usefulness of single nucleotide polymorphism (SNP) array in the detection of genetic causes of 102 DD/ID patients from Fujian (China). Of them, clinically relevant variants (including pathogenic and likely pathogenic), variants of uncertain significance (VOUS), and no clinically relevant variants (including likely benign and benign) were detected in 19, 4 and 79 patients, accounting for 18.6%, 3.9% and 77.5%, respectively, with a diagnostic yield of 18.6% in our study. Furthermore, we divided 19 clinically relevant variants into 4 groups, including chromosome aneuploidy (n = 1); large copy number variants (CNVs) (>10 Mb) (n = 8); known genomic disorders (n = 8), and likely pathogenic CNVs (n = 2). Moreover, we discussed our findings with respect to 4 cases of VOUS. Overall, we confirmed that DD/ID is a genetically heterogeneous condition and emphasized the importance of using genome-wide SNP array in the detection of its genetic causes. Additionally, we provided clinical and molecular data of patients with causal chromosomal aberrations, and discussed the potential implication in DD/ID of genes located within those CNVs or regions of homozygosity.

Early pregnancy loss (EPL) is a common event worldwide. Previous studies show that mitochondrial DNA (mtDNA) copy number (CN) is associated with semen parameters and preimplantation embryo viability, indicating the predictive potential of mtDNA CN for ongoing pregnancy outcomes. However, no relevant study has assessed the relationship between mtDNA CN and EPL. Thus, we aimed to determine whether mtDNA CN and mtDNA 4977-bp deletion rate (DR) in chorionic villous tissue are associated with EPL. Chorionic villous tissue total DNA was extracted from 75 EPL cases and 75 healthy controls. Chromosomal analysis was conducted using copy number variation (CNV) sequencing. The mtDNA CN and DR were measured in samples without pathogenic CNVs. The association between mtDNA CN or DR and EPL risk were estimated using logistic regression. The EPL group had a significantly different mtDNA CN (P 0.001) and DR (P = 0.005) compared to the control group. Both biomarkers were independent risk factors for EPL (CN odds ratio 1.71, 95% confidence interval 1.17 to 2.49, P = 0.005; DR odds ratio 1.07, 95% confidence interval 1.02 to 1.12, P = 0.006). These results suggest that higher mtDNA CN and DR levels are strongly associated with EPL and represent independent risk factors for EPL. Further studies validating these findings and exploring the underlying biological mechanisms are warranted.