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This retrospective cohort study assessed the accessibility of a genetic counselor on uptake of preimplantation genetic testing for aneuploidy (PGT-A) and carrier screening in a single academic Reproductive Endocrinology and Infertility (REI) clinic. A total of 420 patients were evaluated with 219 patients counseled by a REI physician only and 201 patients after the addition of a genetic counselor (GC) to the REI clinic team. Cycles initiated before hiring of a GC (pre-GC) were assessed from June 2018 to December 2018 and after integration of a GC (post-GC) from March 2019 to August 2019. Additionally, information regarding carrier screening was collected if available in the medical record. Results showed more patients utilized PGT-A post-GC (9.5% vs. 5.5%), although the difference between groups did not reach statistical significance (p = 0.12). Individuals who were screened post-GC or who started screening pre-GC and continued screening post-GC were screened for a larger number of conditions than if they were only screened pre-GC (median pre-GC = 3, post-GC = 27, pre- and post-GC = 274; p < 0.0001). The change in practice from using physician-only counseling to counseling with accessibility to a GC did not change the utilization of PGT-A in a single clinic., (© 2023 The Authors. Journal of Genetic Counseling published by Wiley Periodicals LLC on behalf of National Society of Genetic Counselors.)

Purpose: We characterize the clinical and molecular phenotypes of six unrelated individuals with intellectual disability and autism spectrum disorder who carry heterozygous missense variants of the PRKAR1B gene, which encodes the R1β subunit of the cyclic AMP-dependent protein kinase A (PKA)., Methods: Variants of PRKAR1B were identified by single- or trio-exome analysis. We contacted the families and physicians of the six individuals to collect phenotypic information, performed in vitro analyses of the identified PRKAR1B-variants, and investigated PRKAR1B expression during embryonic development., Results: Recent studies of large patient cohorts with neurodevelopmental disorders found significant enrichment of de novo missense variants in PRKAR1B. In our cohort, de novo origin of the PRKAR1B variants could be confirmed in five of six individuals, and four carried the same heterozygous de novo variant c.1003C>T (p.Arg335Trp; NM&#95;001164760). Global developmental delay, autism spectrum disorder, and apraxia/dyspraxia have been reported in all six, and reduced pain sensitivity was found in three individuals carrying the c.1003C>T variant. PRKAR1B expression in the brain was demonstrated during human embryonal development. Additionally, in vitro analyses revealed altered basal PKA activity in cells transfected with variant-harboring PRKAR1B expression constructs., Conclusion: Our study provides strong evidence for a PRKAR1B-related neurodevelopmental disorder., (© 2021. The Author(s).)

T cells can be subdivided into a number of different subsets that are defined by their distinct functions. While the specialization of different T cell subsets is partly achieved by the expression of specific genes, the overall transcriptional profiles of all T cells appear very similar. Alternative mRNA splicing is a mechanism that facilitates greater transcript/protein diversity from a limited number of genes, which may contribute to the functional specialization of distinct T cell subsets. In this study we employ a combination of short-read and long-read sequencing technologies to compare alternative mRNA splicing between the CD4 and CD8 T cell lineages. While long-read technology was effective at assembling full-length alternatively spliced transcripts, the low sequencing depth did not facilitate accurate quantitation. On the other hand, short-read technology was ineffective at assembling full-length transcripts but was highly accurate for quantifying expression. We show that integrating long-read and short-read data together achieves a more complete view of transcriptomic diversity. We found that while the overall usage of transcript isoforms was very similar between the CD4 and CD8 lineages, there were numerous alternative spliced mRNA isoforms that were preferentially used by one lineage over the other. These alternative spliced isoforms included ones with different exon usage, exon exclusion or intron inclusion, all of which are expected to significantly alter the protein sequence., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Aminoacyl-tRNA synthetases (ARSs) are ubiquitous, ancient enzymes that charge amino acids to cognate tRNA molecules, the essential first step of protein translation. Here, we describe 32 individuals from 21 families, presenting with microcephaly, neurodevelopmental delay, seizures, peripheral neuropathy, and ataxia, with de novo heterozygous and bi-allelic mutations in asparaginyl-tRNA synthetase (NARS1). We demonstrate a reduction in NARS1 mRNA expression as well as in NARS1 enzyme levels and activity in both individual fibroblasts and induced neural progenitor cells (iNPCs). Molecular modeling of the recessive c.1633C>T (p.Arg545Cys) variant shows weaker spatial positioning and tRNA selectivity. We conclude that de novo and bi-allelic mutations in NARS1 are a significant cause of neurodevelopmental disease, where the mechanism for de novo variants could be toxic gain-of-function and for recessive variants, partial loss-of-function., (Copyright © 2020. Published by Elsevier Inc.)

Developmental epileptic encephalopathies are devastating disorders characterized by intractable epileptic seizures and developmental delay. Here, we report an allelic series of germline recessive mutations in UGDH in 36 cases from 25 families presenting with epileptic encephalopathy with developmental delay and hypotonia. UGDH encodes an oxidoreductase that converts UDP-glucose to UDP-glucuronic acid, a key component of specific proteoglycans and glycolipids. Consistent with being loss-of-function alleles, we show using patients' primary fibroblasts and biochemical assays, that these mutations either impair UGDH stability, oligomerization, or enzymatic activity. In vitro, patient-derived cerebral organoids are smaller with a reduced number of proliferating neuronal progenitors while mutant ugdh zebrafish do not phenocopy the human disease. Our study defines UGDH as a key player for the production of extracellular matrix components that are essential for human brain development. Based on the incidence of variants observed, UGDH mutations are likely to be a frequent cause of recessive epileptic encephalopathy.

Purpose: To define the clinical characteristics of patients with variants in TCF20, we describe 27 patients, 26 of whom were identified via exome sequencing. We compare detailed clinical data with 17 previously reported patients., Methods: Patients were ascertained through molecular testing laboratories performing exome sequencing (and other testing) with orthogonal confirmation; collaborating referring clinicians provided detailed clinical information., Results: The cohort of 27 patients all had novel variants, and ranged in age from 2 to 68 years. All had developmental delay/intellectual disability. Autism spectrum disorders/autistic features were reported in 69%, attention disorders or hyperactivity in 67%, craniofacial features (no recognizable facial gestalt) in 67%, structural brain anomalies in 24%, and seizures in 12%. Additional features affecting various organ systems were described in 93%. In a majority of patients, we did not observe previously reported findings of postnatal overgrowth or craniosynostosis, in comparison with earlier reports., Conclusion: We provide valuable data regarding the prognosis and clinical manifestations of patients with variants in TCF20.

Background: Biallelic deleterious variants in RTTN, which encodes rotatin, are associated with primary microcephaly, polymicrogyria, seizures, intellectual disability, and primordial dwarfism in human infants., Methods and Results: We performed exome sequencing of an infant with primary microcephaly, pontocerebellar hypoplasia, and intractable seizures and his healthy, unrelated parents. We cultured the infant's fibroblasts to determine primary ciliary phenotype., Results: We identified biallelic variants in RTTN in the affected infant: a novel missense variant and a rare, intronic variant that results in aberrant transcript splicing. Cultured fibroblasts from the infant demonstrated reduced length and number of primary cilia., Conclusion: Biallelic variants in RTTN cause primary microcephaly in infants. Functional characterization of primary cilia length and number can be used to determine pathogenicity of RTTN variants.

Gnathodiaphyseal dysplasia (GDD; OMIM #166260) is an ultra-rare autosomal dominant disorder caused by heterozygous mutation in the anoctamin 5 (ANO5) gene and features fibro-osseous lesions of the jawbones, bone fragility with recurrent fractures, and bowing/sclerosis of tubular bones. The physiologic role of ANO5 is unknown. We report a 5-year-old boy with a seemingly atypical and especially severe presentation of GDD and unique ANO5 mutation. Severe osteopenia was associated with prenatal femoral fractures, recurrent postnatal fractures, and progressive bilateral enlargement of his maxilla and mandible beginning at ~2months-of-age that interfered with feeding and speech and required four debulking operations. Histopathological analysis revealed benign fibro-osseous lesions resembling cemento-ossifying fibromas of the jaw without psammomatoid bodies. A novel, de novo, heterozygous, missense mutation was identified in exon 15 of ANO5 (c.1553G>A; p.Gly518Glu). Our findings broaden the phenotypic and molecular spectra of GDD. Fractures early in life with progressive facial swelling are key features. We assessed his response to a total of 7 pamidronate infusions commencing at age 15months. Additional reports must further elucidate the phenotype, explore any genotype-phenotype correlation, and evaluate treatments., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Calcium/calmodulin-dependent protein kinase II (CAMK2) is one of the first proteins shown to be essential for normal learning and synaptic plasticity in mice, but its requirement for human brain development has not yet been established. Through a multi-center collaborative study based on a whole-exome sequencing approach, we identified 19 exceedingly rare de novo CAMK2A or CAMK2B variants in 24 unrelated individuals with intellectual disability. Variants were assessed for their effect on CAMK2 function and on neuronal migration. For both CAMK2A and CAMK2B, we identified mutations that decreased or increased CAMK2 auto-phosphorylation at Thr286/Thr287. We further found that all mutations affecting auto-phosphorylation also affected neuronal migration, highlighting the importance of tightly regulated CAMK2 auto-phosphorylation in neuronal function and neurodevelopment. Our data establish the importance of CAMK2A and CAMK2B and their auto-phosphorylation in human brain function and expand the phenotypic spectrum of the disorders caused by variants in key players of the glutamatergic signaling pathway., (Copyright © 2017 American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.)

Background: De novo missense variants in CDK13 have been described as the cause of syndromic congenital heart defects in seven individuals ascertained from a large congenital cardiovascular malformations cohort. We aimed to further define the phenotypic and molecular spectrum of this newly described disorder., Methods: To minimise ascertainment bias, we recruited nine additional individuals with CDK13 pathogenic variants from clinical and research exome laboratory sequencing cohorts. Each individual underwent dysmorphology exam and comprehensive medical history review., Results: We demonstrate greater than expected phenotypic heterogeneity, including 33% (3/9) of individuals without structural heart disease on echocardiogram. There was a high penetrance for a unique constellation of facial dysmorphism and global developmental delay, as well as less frequently seen renal and sacral anomalies. Two individuals had novel CDK13 variants (p.Asn842Asp, p.Lys734Glu), while the remaining seven unrelated individuals had a recurrent, previously published p.Asn842Ser variant. Summary of all variants published to date demonstrates apparent restriction of pathogenic variants to the protein kinase domain with clustering in the ATP and magnesium binding sites., Conclusions: Here we provide detailed phenotypic and molecular characterisation of individuals with pathogenic variants in CDK13 and propose management guidelines based upon the estimated prevalence of anomalies identified.

Three diamino, dihetero-phenol ligands were synthesized by sequential Mannich condensations. These ligands were combined with FeCl3 to produce three five-coordinate Fe(III) complexes that are structural models for the enzyme 3,4-PCD. The three Fe(III) complexes were characterized by elemental analysis, single crystal X-ray diffraction studies, UV-vis spectroscopy, and cyclic voltammetry. Combining the Fe(III) complexes with 3,5-di-t-butylcatechol and O2 resulted in oxidative cleavage similar to the function of 3,4-PCD.

We have presented an illustrative case of thrombocytopenic purpura complicating infectious mononucleosis. Steroid therapy appeared to be beneficial although spontaneous recovery cannot be excluded. The use of the Paul-Bunnell heterophil agglutination test is recommended for patients having idiopathic thrombocytopenic purpura to rule out subclinical infectious mononucleosis. It is suggested that this syndrome be treated with the expectancy of long-term remissions. Steroids appear to be of benefit. Platelet recovery is usually complete in less than 60 days. Splenectomy should not be considered until at least two months have passed. Chronic thrombocytopenia is an unlikely complication.