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Objective: Prenatally detected central nervous system (CNS) anomalies present a diagnostic challenge. In this study, we compared the diagnostic yield of exome sequencing (ES) and chromosomal microarray analysis (CMA) in fetuses with a major CNS anomaly.Methods: This was a retrospective study of 114 cases referred for genetic evaluation following termination of pregnancy (TOP) due to a major CNS anomaly detected on prenatal ultrasound. All fetuses were first analyzed by CMA. All CMA-negative cases were offered ES. CMA-positive cases were reanalyzed using ES to assess its ability to detect copy-number variants (CNVs).Results: CMA identified a pathogenic or likely pathogenic (P/LP) CNV in 11/114 (10%) cases. Eighty-six CMA-negative cases were analyzed using ES, which detected P/LP sequence variants in 38/86 (44%). Among recurrent cases (i.e. cases with a previously affected pregnancy), the incidence of P/LP sequence variants was non-significantly higher compared with non-recurrent ones (12/19 (63%) vs 26/67 (39%); P = 0.06). Among the 38 cases with an ES diagnosis, 20 (53%) were inherited and carried a significant risk of recurrence. Reanalysis of 10 CMA-positive cases by ES demonstrated that the bioinformatics pipeline used for sequence variant analysis also detected all P/LP CNVs, as well as three previously known non-causative CNVs.Conclusions: In our study, ES provided a high diagnostic yield (> 50%) in fetuses with severe CNS structural anomalies, which may have been partly due to the highly selected case series that included post-TOP cases from a specialist referral center. These data suggest that ES may be considered as a first-tier test for the prenatal diagnosis of major fetal CNS anomalies, detecting both P/LP sequence variants and CNVs. This is of particular importance given the time constraints of an ongoing pregnancy and the risk of recurrence in future pregnancies. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology. [ABSTRACT FROM AUTHOR]

This has been discussed in detail in a recent systematic review by Mellis I et al i .[2], demonstrating that the incremental diagnostic yield of ES over CMA/karyotyping was 15% for non-selected fetal anomalies, 42% for selected anomalies and 17% for CNS anomalies. While patients were offered concurrent chromosomal microarray analysis (CMA) and exome sequencing (ES), most opted for termination of pregnancy even before receiving a genetic test result due to the severity of anomalies and because ES in pregnancy is currently not covered by the Israeli healthcare system. Even if the fetal phenotype may not appear to be severe enough to warrant termination of pregnancy, a genetic test result may point to a severe neurodevelopmental issue that has only mild physical manifestations. [Extracted from the article]

The authors of the article titled "Unique prenatal manifestations of biallelic NDUFAF5 variants: expansion of phenotype" respond to comments made by Dr. Finsterer. They clarify that their study did not report on cases of intrauterine fetal death, but rather on cases of termination due to fetal anomalies. They also explain that functional or biochemical testing is not mandatory for determining variant pathogenicity according to the American College of Medical Genetics and Genomics guidelines. The authors provide evidence supporting the pathogenicity of the NDUFAF5 variants they studied and acknowledge the need for further research on one of the variants. They assert that their study contributes to the understanding of prenatal presentations of NDUFAF5-associated disorders and emphasize the challenges of studying prenatal phenotypes. The authors address Dr. Finsterer's mention of other possible abnormalities associated with NDUFAF5 variants and state that the lack of demonstration does not negate their assumption that these variants are causative of the congenital anomalies described in their study. They also clarify that family history and parental carrier status were included in their original manuscript. [Extracted from the article]

The article presents the author's views on the non-invasive prenatal testing (NIPT) for pregnant women who want to detect trisomy 21 in their unborn child. It states that NIPT improve the quality of prenatal testing for fetal abnormalities. It further discusses aneuploidy screening, chromosomal microarray analysis and testing in pregnancy.

Arabidopsis VRN genes mediate vernalization, the process by which a long period of cold induces a mitotically stable state that leads to accelerated flowering during later development. VRN1 encodes a protein that binds DNA in vitro in a non-sequence-specific manner and functions in stable repression of the major target of the vernalization pathway, the floral repressor FLC. Overexpression of VRN1 reveals a vernalization-independent function for VRN1, mediated predominantly through the floral pathway integrator FT, and demonstrates that VRN1 requires vernalization-specific factors to target FLC. [ABSTRACT FROM AUTHOR]

Investigates the mediation of epigenetic regulation of vernalization (VRN) in arabidopsis by VRN2. Analysis of plant growth conditions, vernalization treatments and flowering time; Administration of genetic and physical mapping; Prediction and identification of genes.

Objective: Mitochondrial complex‐I deficiency, nuclear type 16, is a rare autosomal recessive disorder caused by biallelic pathogenic variants in NDUFAF5 (C20orf7) (OMIM 618238). The aim of this study was to describe a severe early prenatal manifestation of this disorder, which was previously considered to occur only postnatally. Methods: This was a multicenter retrospective case series including five fetuses from three non‐related families, which shared common sonographic abnormalities, including brain cysts, corpus callosal malformations, non‐immune hydrops fetalis and growth restriction. Genetic evaluation included chromosomal microarray analysis and exome sequencing. Two fetuses from the same family were also available for pathology examination, including electron microscopy. Results: Chromosomal microarray analysis revealed no chromosomal abnormality in any of the tested cases. Trio exome sequencing demonstrated that three affected fetuses from three unrelated families were compound heterozygous or homozygous for likely pathogenic variants in NDUFAF5. No other causative variants were detected. The association between NDUFAF5 variants and fetal malformations was further confirmed by segregation analysis. Histological evaluation of fetal tissues and electron microscopy of the skeletal muscle, liver, proximal tubules and heart demonstrated changes that resembled postmortem findings in patients with mitochondrial depletion disorders as well as previously undescribed findings. Conclusions: Mitochondrial complex‐I deficiency and specifically biallelic mutations in NDUFAF5 have a role in abnormal fetal development, presenting with severe congenital malformations. Mitochondrial complex‐I disorders should be considered in the differential diagnosis of corpus callosal malformations and brain cysts, especially when associated with extracranial abnormalities, such as fetal growth restriction and non‐immune hydrops fetalis. © 2023 International Society of Ultrasound in Obstetrics and Gynecology. Linked article: There is a comment on this article by Finsterer. Click here to view the Correspondence. [ABSTRACT FROM AUTHOR]

Objectives: To determine the incremental diagnostic yield of exome sequencing (ES) after negative chromosomal microarray analysis (CMA) in cases of prenatally diagnosed agenesis of the corpus callosum (ACC) and to identify the associated genes and variants. Methods: A systematic search was performed to identify relevant studies published up until June 2022 using four databases: PubMed, SCOPUS, Web of Science and The Cochrane Library. Studies in English reporting on the diagnostic yield of ES following negative CMA in prenatally diagnosed partial or complete ACC were included. Authors of cohort studies were contacted for individual participant data and extended cohorts were provided for two of them. The increase in diagnostic yield with ES for pathogenic/likely pathogenic (P/LP) variants was assessed in all cases of ACC, isolated ACC, ACC with other cranial anomalies and ACC with extracranial anomalies. To identify all reported genetic variants, the systematic review included all ACC cases; however, for the meta‐analysis, only studies with ≥ three ACC cases were included. Meta‐analysis of proportions was employed using a random‐effects model. Quality assessment of the included studies was performed using modified Standards for Reporting of Diagnostic Accuracy criteria. Results: A total of 28 studies, encompassing 288 prenatally diagnosed ACC cases that underwent ES following negative CMA, met the inclusion criteria of the systematic review. We classified 116 genetic variants in 83 genes associated with prenatal ACC with a full phenotypic description. There were 15 studies, encompassing 268 cases, that reported on ≥ three ACC cases and were included in the meta‐analysis. Of all the included cases, 43% had a P/LP variant on ES. The highest yield was for ACC with extracranial anomalies (55% (95% CI, 35–73%)), followed by ACC with other cranial anomalies (43% (95% CI, 30–57%)) and isolated ACC (32% (95% CI, 18–51%)). Conclusions: ES demonstrated an incremental diagnostic yield in cases of prenatally diagnosed ACC following negative CMA. While the greatest diagnostic yield was observed in ACC with extracranial anomalies and ACC with other central nervous system anomalies, ES should also be considered in cases of isolated ACC. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology. [ABSTRACT FROM AUTHOR]

In addition to ventriculomegaly, abnormal corpus callosum and adducted thumbs, fetal MRI has also detected diencephalic and midbrain-hindbrain malformations in most fetuses affected by the L1 syndrome. L1 syndrome includes a spectrum of X-linked disorders caused by pathogenic variants of L1CAM gene, which encodes a cell adhesion molecule involved in the central nervous system (CNS) development. In addition to the evaluation of lateral ventricles, corpus callosum and cortical development, thalami and midbrain-hindbrain were investigated. [Extracted from the article]

OC12.05: Early second trimester diagnosis of fetal midbrain-hindbrain malformations: a transvaginal neurosonographic study To describe the clinical and neurosonographic features of fetal midbrain-hindbrain (MBHB malformation diagnosed at 14-18 weeks. The MBHB abnormalities include; kinking of the brainstem (KBS) (n = 3), Joubert syndrome (JS) (n = 2), aqueductal stenosis (AS) (n = 11), rhombencephalosynapsis (RES) (n = 3), "open" fourth ventricle (OFV) (n = 6), and Mobius syndrome (MS) (n = 1). [Extracted from the article]

Background: Primary analysis of the double-blind, phase III Efficacy of XL184 (Cabozantinib) in Advanced Medullary Thyroid Cancer (EXAM) trial demonstrated significant improvement in progression-free survival with cabozantinib versus placebo in patients with progressive medullary thyroid cancer (MTC). Final analysis of overall survival (OS), a key secondary endpoint, was carried out after long-term follow-up. Patients and methods: EXAM compared cabozantinib with placebo in 330 patients with documented radiographic progression of metastatic MTC. Patients were randomized (2:1) to cabozantinib (140 mg/day) or placebo. Final OS and updated safety data are reported. Results: Minimum follow-up was 42 months. Kaplan-Meier analysis showed a 5.5-month increase in median OS with cabozantinib versus placebo (26.6 versus 21.1 months) although the difference did not reach statistical significance [stratified hazard ratio (HR), 0.85; 95% confidence interval (CI), 0.64-1.12; P=0.24]. In an exploratory assessment of OS, progression-free survival, and objective response rate, cabozantinib appeared to have a larger treatment effect in patients with RET M918T mutation-positive tumors compared with patients not harboring this mutation. For patients with RET M918T-positive disease, median OS was 44.3 months for cabozantinib versus 18.9 months for placebo [HR, 0.60; 95% CI, 0.38-0.94; P=0.03 (not adjusted for multiple subgroup analyses)], with corresponding values of 20.2 versus 21.5 months (HR, 1.12; 95% CI, 0.70-1.82; P=0.63) in the RET M918T-negative subgroup. Median treatment duration was 10.8 months with cabozantinib and 3.4 months with placebo. The safety profile for cabozantinib remained consistent with that of the primary analysis. Conclusion: The secondary end point was not met in this final OS analysis from the trial of cabozantinib in patients with metastatic, radiographically progressive MTC. A statistically nonsignificant increase in OS was observed for cabozantinib compared with placebo. Exploratory analyses suggest that patients with RET M918T-positive tumors may experience a greater treatment benefit with cabozantinib. [ABSTRACT FROM AUTHOR]

In breast cancer the human epidermal growth factor receptor 2 (HER2) is an important target for a number of different HER2 inhibitors. Different slide-based assays are available for assessment of treatment eligibility, which include fluorescence in situ hybridization (FISH) or other in situ hybridization (ISH) methods for assessment of the HER2 gene status. Here we report a summary of the validation data on HER2 IQFISH pharmDx™ (Dako Omnis), a newly developed assay for the automated staining platform Dako Omnis. The assay uses a non-toxic buffer that significantly reduces the hybridization time, which results in a total turnaround time of 3½ to 4 h from deparaffinization to counting of the gene and centromere signals. The data reported in the current summary covers method comparison, assessment of staining quality, observer-to-observer reproducibility as well as reproducibility within and between laboratories. Based on data from the different studies it was concluded that HER2 IQFISH pharmDx (Dako Omnis) is a reliable and robust assay with a high precision that is at least comparable to the manual HER2 IQFISH pharmDx™ assay and the PathVysion ® HER-2 DNA Probe Kit. [ABSTRACT FROM AUTHOR]

The article considers the benefits of contingent screening against primary screening by cell-free DNA testing. Topics discussed include non-invasive prenatal testing (NIPT) via cell-free DNA analysis, NIPT implementation in public-health-based programs, and the lack of evidence for additional perceived benefits of serum screening or nuchal translucency (NT) measurement.

Variants of unknown significance (VUS) poses a dilemma in prenatal genetic testing and counselling. Methods Cases were selected from a cohort of 87 patients who underwent TOP for major CNS anomalies and presented VUS either in genetic assessment. [Extracted from the article]

Fetal imaging findings (US, MRI or both) of fetuses with copy number variants (CNVs) or pathogenic/likely pathogenic sequence variants (SVs) were compared to the classical phenotype described by the literature. OC01.02: Genotype-phenotype correlation in fetuses with major brain malformations using whole-exome sequencing When performing fetal ultrasound (US) we are confronted with the difficult task of finding a correlation between imaging findings, diagnosis and prognosis. [Extracted from the article]

BACKGROUND: The pathologic features of Down syndrome are assumed to be the result of over-expression of genes located on chromosome 21 and/or a more global transcriptional misregulation that crosses chromosomal borders. [ABSTRACT FROM PUBLISHER]

OC06.07: Maternal plasma genome-wide cell-free DNA testing can detect fetal aneuploidy in pregnancy loss and can be used to guide further work-up in recurrent losses However, the most common cause of miscarriage, even in RPLs, is random chromosomal aberrations (trisomy, monosomy, triploidy). We suggest that cfDNA-based testing serve to guide management in RPLs: if cfDNA in the 2nd and subsequent RPL demonstrates aneuploidy, no further action is taken; if cfDNA demonstrates an unbalanced rearrangement, parental karyotypes is recommended; and if no abnormality is detected, then the recommended RPL workup is performed. [Extracted from the article]

Aim: Carriers of balanced reciprocal translocations have an increased risk for repeated implantation failures and offspring with congenital malformations. Preimplantation genetic diagnosis (PGD) for such carriers ensures the transfer of chromosomally balanced embryos, and can significantly increase the probability of a healthy offspring. Research into chromosomal imbalances is limited since some segregation variants, particularly monosomies, are embryonically lethal. In the current work, we aimed to derive a HESC line that harbors partial monosomy, with the intent of studying developmental abnormalities and gene dosage effects. Methods & Results: Following PGD-FISH, three embryos with an unbalanced translocation developed into expanded blastocysts, and one HESC line with der(11)t(11;22)(q23;q12) was established, labeled Lis05_t(11;22). Lis05_t(11;22) harbored a partial monosomy, but it was still able to self-renew in vitro while remaining undifferentiated (currently at P53), demonstrating a typical HESC line morphology and expressing a panel of pluripotent markers. Full karyotyping confirmed partial monosomies 11 and 22 with no other chromosomal aberrations. Cell proliferation and colony formation assays demonstrated that even though Lis05_t(11;22) line demonstrated a self-renewal capacity, its proliferation rate was significantly lower than that of a wild type HESC (WT-HESC) line. Although the Lis05_t(11;22) line carried a non-balanced translocation known to be lethal during early embryonic development, it spontaneously differentiated into embryoid bodies. However, the expression levels of nine specific markers for the three germ layers and the trophectoderm, varied considerably in the Lis05_t(11;22)-differentiated cells compared to WT-HESCs, as demonstrated by qRT-PCR. Comparison of gene expression patterns between the partial monosomy Lis05_t(11;22) and the WT-HESCs by Affymetrix cDNA micro-array analysis revealed differential gene expression in chromosomes and regions other than the monosomic ones, of genes related mainly to development. Discussion: Monosomic HESC lines derived from unbalanced translocated embryos are a valuable model for studying single gene dosage effects as well as the pathophysiological mechanisms underlying developmental abnormalities. [ABSTRACT FROM AUTHOR]