CADD v1.7: using protein language models, regulatory CNNs and other nucleotide-level scores to improve genome-wide variant predictions

Association Analysis of Rare CNTN5 Variants With Autism Spectrum Disorder in a Japanese Population

BACKGROUND

Contactin-5 (CNTN5), a neural adhesion molecule involved in synaptogenesis and synaptic maturation in the auditory pathway, has been associated with the pathophysiology of autism spectrum disorder (ASD), particularly hyperacusis. To investigate the role of rare CNTN5 variants in ASD susceptibility, we performed resequencing and association analysis in a Japanese population.

METHODS

We resequenced the CNTN5 coding regions in 302 patients with ASD and prioritized rare putatively damaging variants. The prioritized variants were then genotyped in 313 patients with ASD and 1065 controls. Subsequently, we conducted an association study of selected variants with ASD in 614 patients with ASD and 61 057 controls. Clinical data were reviewed for patients carrying prioritized variants.

RESULTS

Through resequencing, we prioritized three rare putatively damaging missense variants (W69G, I227L, and L1000S) in patients with ASD. Although we found a nominally significant association between the I227L variant and ASD, it did not remain significant after post hoc correction. Hyperacusis was found in three out of nine patients carrying prioritized variants.

CONCLUSION

This study does not provide evidence for the contribution of rare CNTN5 variants to the genetic etiology of ASD in the Japanese population.

Immunotherapy Responsive Recurrent Post-Infectious Ataxia Associated With Recurrent ATP2B2 Gene Variant

Objectives

We detail a case of recurrent, postinfectious, cerebellar ataxia associated with a likely pathogenic previously documented gene variant in ATP2B2.

Methods

The patient was identified after her second hospitalization for postinfectious cerebellar ataxia. Genetic testing was performed after discharge.

Results

An 11-year-old girl with 1 prior episode of self-resolving parainfectious acute cerebellar ataxia at age 4 years presented with acute-onset ataxia, dysarthria, and gait instability in the setting of influenza A infection. The patient had CSF pleocytosis but negative influenza PCR and antibody detection in the CSF. Because of clinical deterioration, she received empiric IV methylprednisolone without improvement. She was subsequently administered IVIg and improved dramatically over the subsequent 7 days. The patient was found to have a rare de novo ATP2B2 gene (c.3028G>A, p.(Glu1010Lys)) variant previously reported in the literature. The variant was analyzed to have a Combined Annotation Dependent Depletion score of 33 and Polyphen-2 score of 1.0 and was determined to be likely pathogenic according to American College of Medical Genetics PP3 and PM2 criterion.

Discussion

Recurrent episodes of cerebellar ataxia are an especially rare occurrence, and genetic testing may be warranted in these individuals. It is possible that immunotherapy with IVIg may augment clinical outcomes in those with pathogenic ATP2B2 gene variants.

Genetic Analysis of Heterotaxy in a Consanguineous Cohort

Heterotaxy (HTX) is a group of clinical conditions with a shared pathology of dislocation of one or more organs along the left-right axis. The etiology of HTX is tremendously heterogeneous spanning environmental factors, chromosomal aberrations, mono/oligogenic variants, and complex inheritance. However, in the vast majority of cases, the etiology of HTX remains elusive. Here, we sought to describe the yield of genetic analysis and spectrum of variants in HTX in our highly consanguineous population. Twenty-four affected individuals, from 19 unrelated families, were consecutively recruited. Genetic analysis, with exome sequencing, genome sequencing, or multigene panel, detected 9 unique variants, 7 of which were novel, in 8 genes known to be implicated in autosomal recessive form of HTX (C1orf127, CCDC39, CIROP, DNAAF3, DNAH5, DNAH9, MMP21, and MNS1) providing a yield of 42.1%. Of note, 7 of the 9 variants were homozygous, while 2 were inherited in compound heterozygosity, including a heterozygous CNV deletion. A search for candidate genes in negative cases did not reveal a plausible variant. Our work demonstrates a relatively high yield of genetic testing in HTX in a consanguineous population with an enrichment of homozygous variants. The significant genetic heterogeneity observed herewith underscores the complex developmental mechanisms implicated in the pathogenesis of HTX and supports adopting a genome-wide analysis in the diagnostic evaluation of HTX.

Evaluating pathogenicity of variants of unknown significance in APP, PSEN1, and PSEN2

Autosomal dominant Alzheimer's disease (ADAD) is driven by rare variants in APP, PSEN1, and PSEN2. Although more than 200 pathogenic variants in these genes are known to cause ADAD, other variants are benign, may act as risk factors, or may even reduce Alzheimer's disease risk (e.g. protective). Classifying novel variants in APP, PSEN1, or PSEN2 as pathogenic, risk, benign, or protective is a critical step in evaluating disease risk profiles which further impacts eligibility for clinical trials focused on the ADAD population. Here, we classify 53 novel variants in APP, PSEN1, and PSEN2 based on bioinformatic data and cell-based assays. We identified 6 benign variants, 2 risk variants, and 32 likely pathogenic variants. Thirteen variants were associated with reduced Aβ levels in cell-based assays, consistent with a potential protective effect. Together, this study highlights the complexities associated with classification of rare variants in ADAD genes.

A network-based systems genetics framework identifies pathobiology and drug repurposing in Parkinson's disease

Parkinson's disease (PD) is the second most prevalent neurodegenerative disorder. However, current treatments only manage symptoms and lack the ability to slow or prevent disease progression. We utilized a systems genetics approach to identify potential risk genes and repurposable drugs for PD. First, we leveraged non-coding genome-wide association studies (GWAS) loci effects on five types of brain-specific quantitative trait loci (xQTLs, including expression, protein, splicing, methylation and histone acetylation) under the protein-protein interactome (PPI) network. We then prioritized 175 PD likely risk genes (pdRGs), such as SNCA, CTSB, LRRK2, DGKQ, and CD44, which are enriched in druggable targets and differentially expressed genes across multiple human brain-specific cell types. Integrating network proximity-based drug repurposing and patient electronic health record (EHR) data observations, we identified Simvastatin as being significantly associated with reduced incidence of PD (hazard ratio (HR) = 0.91 for fall outcome, 95% confidence interval (CI): 0.87-0.94; HR = 0.88 for dementia outcome, 95% CI: 0.86-0.89) after adjusting for 267 covariates. In summary, our network-based systems genetics framework identifies potential risk genes and repurposable drugs for PD and other neurodegenerative diseases if broadly applied.

Compound Heterozygous p.(R124C) (Classic Lattice Corneal Dystrophy) and p.(R124H) (Granular Corneal Dystrophy Type 2) in TGFBI: Phenotype, Genotype, and Treatment

(1) Background: The phenotypes of classic lattice corneal dystrophy (LCD) and granular corneal dystrophy type 2 (GCD2) that result from abnormalities in transforming growth factor β-induced gene (TGFBI) have previously been described. The phenotype of compound heterozygous classic LCD and GCD2, however, has not yet been reported. (2) Case report: A 39-year-old male (proband) presented to our clinic complaining of decreased vision bilaterally. A slit-lamp examination revealed corneal opacities consistent with classic LCD. Contrast sensitivity (CS) was decreased. A genetic analysis performed with commercially available real-time polymerase chain reaction (PCR) showed both homozygous classic LCD and homozygous GCD2. Sanger sequencing performed in our lab suggested compound heterozygosity for c.370C>T and c.371G>A variants, which was confirmed by the TA cloning of exon 4 of TGFBI and sequencing of clones. Phototherapeutic keratectomy (PTK) was performed on the right eye of the proband, and the CS improved. (3) Conclusions: Compound heterozygous classic LCD and GCD2 produces clinical findings like that of severe, classic LCD. PTK can improve VA and CS, delaying the need for keratoplasty.

RLIM-specific activity reporters define variant pathogenicity in Tonne-Kalscheuer syndrome

Tonne-Kalscheuer syndrome (TOKAS; MIM: 300978) is an X-linked recessive disorder with devastating consequences for patients, such as intellectual disability, developmental delay, and multiple congenital abnormalities. TOKAS is associated with hemizygous variants in the RLIM gene, which encodes a RING-type E3 ubiquitin ligase. The current sustained increase in reported RLIM variants of uncertain significance creates an urgent need to develop assays that can screen these variants and experimentally determine their pathogenicity and disease association. Here, we engineered flow cytometry-based RLIM-specific reporters to measure RLIM activity in TOKAS. This paper describes the design and use of RLIM-specific reporters to determine the pathogenicity of a TOKAS RLIM gene variant. Our data demonstrate that RLIM-specific flow cytometry reporters based on either the full length or a degron region of the substrate REX1 measure RLIM activity in cells. Further, we describe the TOKAS variant RLIM p.Asn581Lys and, using reporter assays, determine that it disrupts RLIM catalytic activity. These data reveal how the p.Asn581Lys variant impairs RLIM function and suggests pathogenic mechanisms. The use of RLIM-specific reporters will greatly accelerate the resolution of variants of uncertain significance and disease association in TOKAS.

Introduction to androgenetics: terminology, approaches, and impactful studies across 60 years

Across six decades, androgenetics has consistently concentrated on discovering genetic causes and enhancing the molecular diagnostics of male infertility, disorders of sex development, and their broader implications on health, such as cancer and other comorbidities. Despite vast clinical knowledge, the training of andrologists often lacks fundamental basics in medical genetics. This work, as part of the Special Issue of Andrology "Genetics in Andrology", provides the core terminology in medical genetics and technological advancements in genomics, required to understand the ever-progressing research in the field. It also gives an overview of study designs and approaches that have frequently led to discoveries in androgenetics. The rapid progress in the methodological toolbox in human genetics is illustrated by numerous examples of impactful androgenetic studies over 60 years, and their clinical implications.

Expanding the Molecular Spectrum of MMP21 Missense Variants: Clinical Insights and Literature Review

BACKGROUND/OBJECTIVES

The failure of physiological left-right (LR) patterning, a critical embryological process responsible for establishing the asymmetric positioning of internal organs, leads to a spectrum of congenital abnormalities characterized by laterality defects, collectively known as "heterotaxy". MMP21 biallelic variants have recently been associated with heterotaxy syndrome and congenital heart defects (CHD). However, the genotype-phenotype correlations and the underlying pathogenic mechanisms remain poorly understood.

METHODS

Patients harboring biallelic MMP21 missense variants who underwent diagnostic genetic testing for CHD or heterotaxy were recruited at the Institute for Maternal and Child Health-I.R.C.C.S. "Burlo Garofolo". Additionally, a literature review on MMP21 missense variants was conducted, and clinical data from reported patients, along with molecular data from in silico and modeling tools, were collected.

RESULTS

A total of 18 MMP21 missense variants were reported in 26 patients, with the majority exhibiting CHD (94%) and variable extra-cardiac manifestations (64%). In our cohort, through Whole-Exome Sequencing (WES) analysis, the missense p.(Met301Ile) variant was identified in two unrelated patients, who both presented with heterotaxy syndrome.

CONCLUSIONS

Our comprehensive analysis of MMP21 missense variants supports the pathogenic role of the p.(Met301Ile) variant and provides significant insights into the disease pathogenesis. Specifically, missense variants are distributed throughout the gene without clustering in specific regions, and phenotype comparisons between patients carrying missense variants in compound heterozygosity or homozygosity do not reveal significant differences. These findings may suggest a potential loss-of-function mechanism for MMP21 missense variants, especially those located in the catalytic domain, and highlight their critical role in the pathogenesis of heterotaxy syndrome.

High-coverage whole-genome sequencing of a Jakun individual from the "Orang Asli" Proto-Malay subtribe from Peninsular Malaysia

Jakun, a Proto-Malay subtribe from Peninsular Malaysia, is believed to have inhabited the Malay Archipelago during the period of agricultural expansion approximately 4 thousand years ago (kya). However, their genetic structure and population history remain inconclusive. In this study, we report the genome structure of a Jakun female, based on whole-genome sequencing, which yielded an average coverage of 35.97-fold. We identified approximately 3.6 million single-nucleotide variations (SNVs) and 517,784 small insertions/deletions (indels). Of these, 39,916 SNVs were novel (referencing dbSNP151), and 10,167 were nonsynonymous (nsSNVs), spanning 5674 genes. Principal Component Analysis (PCA) revealed that the Jakun genome sequence closely clustered with the genomes of the Cambodians (CAM) and the Metropolitan Malays from Singapore (SG_MAS). The ADMIXTURE analysis further revealed potential admixture from the EA and North Borneo populations, as corroborated by the results from the F3, F4, and TreeMix analyses. Mitochondrial DNA analysis revealed that the Jakun genome carried the N21a haplogroup (estimated to have occurred ~19 kya), which is commonly found among Malays from Malaysia and Indonesia. From the whole-genome sequence data, we identified 825 damaging and deleterious nonsynonymous single-nucleotide polymorphisms (nsSNVs) affecting 720 genes. Some of these variants are associated with age-related macular degeneration, atrial fibrillation, and HDL cholesterol level. Additionally, we located a total of 3310 variants on 32 core adsorption, distribution, metabolism, and elimination (ADME) genes. Of these, 193 variants are listed in PharmGKB, and 21 are nsSNVs. In summary, the genetic structure identified in the Jakun individual could enhance the mapping of genetic variants for disease-based population studies and further our understanding of the human migration history in Southeast Asia.

GoFCards: an integrated database and analytic platform for gain of function variants in humans

Gain-of-function (GOF) variants, which introduce new or amplify protein functions, are essential for understanding disease mechanisms. Despite advances in genomics and functional research, identifying and analyzing pathogenic GOF variants remains challenging owing to fragmented data and database limitations, underscoring the difficulty in accessing critical genetic information. To address this challenge, we manually reviewed the literature, pinpointing 3089 single-nucleotide variants and 72 insertions and deletions in 579 genes associated with 1299 diseases from 2069 studies, and integrated these with the 3.5 million predicted GOF variants. Our approach is complemented by a proprietary scoring system that prioritizes GOF variants on the basis of the evidence supporting their GOF effects and provides predictive scores for variants that lack existing documentation. We then developed a database named GoFCards for general geneticists and clinicians to easily obtain GOF variants in humans (http://www.genemed.tech/gofcards). This database also contains data from >150 sources and offers comprehensive variant-level and gene-level annotations, with the aim of providing users with convenient access to detailed and relevant genetic information. Furthermore, GoFCards empowers users with limited bioinformatic skills to analyze and annotate genetic data, and prioritize GOF variants. GoFCards offers an efficient platform for interpreting GOF variants and thereby advancing genetic research.

Ensembl 2025

Ensembl (www.ensembl.org) is an open platform integrating publicly available genomics data across the tree of life with a focus on eukaryotic species related to human health, agriculture and biodiversity. This year has seen a continued expansion in the number of species represented, with >4800 eukaryotic and >31 300 prokaryotic genomes available. The new Ensembl site, currently in beta, has continued to develop, currently holding >2700 eukaryotic genome assemblies. The new site provides genome, gene, transcript, homology and variation views, and will replace the current Rapid Release site; this represents a key step towards provision of a single integrated Ensembl site. Additional activities have included developing improved regulatory annotation for human, mouse and agricultural species, and expanding the Ensembl Variant Effect Predictor tool. To learn more about Ensembl, help and documentation are available along with an extensive training program that can be accessed via our training pages.

Association of Novel Pathogenic Variant (p. Ile366Asn) in PLA2G6 Gene with Infantile Neuroaxonal Dystrophy

A couple presented to the office with an apparently healthy infant for a thorough clinical assessment, as they had previously lost two male children to a neurodegenerative disorder. They also reported the death of a male cousin abroad with a comparable condition. We aimed to evaluate a novel coding pathogenic variant c.1097T>A, PLA2G6, within the affected family, previously identified in a deceased cousin, but its clinical significance remained undetermined. A 200 bp PCR product of target genome (including codon 366 of PLA2G6) was amplified followed by enzymatic digestion (MboI) and sequencing. Structural pathogenic variant analysis was performed using PyMOL 2.5.4. In RFLP analysis, the mutant-type allele produced a single band of 200 bp, and the wild-type allele manifested as two bands of 112 bp and 88 bp. The pathogenic variant was identified in nine family members, including two heterozygous couples with consanguineous marriages resulting in affected children. It was predicted to be deleterious by multiple bioinformatic tools. The substitution of nonpolar isoleucine with polar asparagine of iPLA2 (Ile366Asn) resulted in a eense pathogenic variant (ATC>AAC). A missense variant (p. Ile366Asn) in the PLA2G6 gene is associated with clinically evident infantile neuroaxonal dystrophy, which is transmitted in an autosomal recessive pattern, and is also predicted to be dysfunctional by bioinformatic analyses.

Chromosome X-wide common variant association study in autism spectrum disorder

Autism spectrum disorder (ASD) displays a notable male bias in prevalence. Research into rare (<0.1) genetic variants on the X chromosome has implicated over 20 genes in ASD pathogenesis, such as MECP2, DDX3X, and DMD. The "female protective effect" in ASD suggests that females may require a higher genetic burden to manifest symptoms similar to those in males, yet the mechanisms remain unclear. Despite technological advances in genomics, the complexity of the biological nature of sex chromosomes leaves them underrepresented in genome-wide studies. Here, we conducted an X-chromosome-wide association study (XWAS) using whole-genome sequencing data from 6,873 individuals with ASD (82% males) across Autism Speaks MSSNG, Simons Simplex Collection (SSC), and Simons Powering Autism Research (SPARK), alongside 8,981 population controls (43% males). We analyzed 418,652 X chromosome variants, identifying 59 associated with ASD (p values 7.9 × 10-6 to 1.51 × 10-5), surpassing Bonferroni-corrected thresholds. Key findings include significant regions on Xp22.2 (lead SNP rs12687599, p = 3.57 × 10-7) harboring ASB9/ASB11 and another encompassing DDX53 and the PTCHD1-AS long non-coding RNA (lead SNP rs5926125, p = 9.47 × 10-6). When mapping genes within 10 kb of the 59 most significantly associated SNPs, 91 genes were found, 17 of which yielded association with ASD (GRPR, AP1S2, DDX53, HDAC8, PCDH19, PTCHD1, PCDH11X, PTCHD1-AS, DMD, SYAP1, CNKSR2, GLRA2, OFD1, CDKL5, GPRASP2, NXF5, and SH3KBP1). FGF13 emerged as an X-linked ASD candidate gene, highlighted by sex-specific differences in minor allele frequencies. These results reveal significant insights into X chromosome biology in ASD, confirming and nominating genes and pathways for further investigation.

Biallelic variation in the choline and ethanolamine transporter FLVCR1 underlies a severe developmental disorder spectrum

PURPOSE

FLVCR1 encodes a solute carrier protein implicated in heme, choline, and ethanolamine transport. Although Flvcr1-/- mice exhibit skeletal malformations and defective erythropoiesis reminiscent of Diamond-Blackfan anemia (DBA), biallelic FLVCR1 variants in humans have previously only been linked to childhood or adult-onset ataxia, sensory neuropathy, and retinitis pigmentosa.

METHODS

We identified individuals with undiagnosed neurodevelopmental disorders and biallelic FLVCR1 variants through international data sharing and characterized the functional consequences of their FLVCR1 variants.

RESULTS

We ascertained 30 patients from 23 unrelated families with biallelic FLVCR1 variants and characterized a novel FLVCR1-related phenotype: severe developmental disorders with profound developmental delay, microcephaly (z-score -2.5 to -10.5), brain malformations, epilepsy, spasticity, and premature death. Brain malformations ranged from mild brain volume reduction to hydranencephaly. Severely affected patients share traits, including macrocytic anemia and skeletal malformations, with Flvcr1-/- mice and DBA. FLVCR1 variants significantly reduce choline and ethanolamine transport and/or disrupt mRNA splicing.

CONCLUSION

These data demonstrate a broad FLVCR1-related phenotypic spectrum ranging from severe multiorgan developmental disorders resembling DBA to adult-onset neurodegeneration. Our study expands our understanding of Mendelian choline and ethanolamine disorders and illustrates the importance of anticipating a wide phenotypic spectrum for known disease genes and incorporating model organism data into genome analysis to maximize genetic testing yield.

PSAP-Genomic-Regions: A Method Leveraging Population Data to Prioritize Coding and Non-Coding Variants in Whole Genome Sequencing for Rare Disease Diagnosis

The introduction of Next-Generation Sequencing technologies in the clinics has improved rare disease diagnosis. Nonetheless, for very heterogeneous or very rare diseases, more than half of cases still lack molecular diagnosis. Novel strategies are needed to prioritize variants within a single individual. The Population Sampling Probability (PSAP) method was developed to meet this aim but only for coding variants in exome data. Here, we propose an extension of the PSAP method to the non-coding genome called PSAP-genomic-regions. In this extension, instead of considering genes as testing units (PSAP-genes strategy), we use genomic regions defined over the whole genome that pinpoint potential functional constraints. We conceived an evaluation protocol for our method using artificially generated disease exomes and genomes, by inserting coding and non-coding pathogenic ClinVar variants in large data sets of exomes and genomes from the general population. PSAP-genomic-regions significantly improves the ranking of these variants compared to using a pathogenicity score alone. Using PSAP-genomic-regions, more than 50% of non-coding ClinVar variants were among the top 10 variants of the genome. On real sequencing data from six patients with Cerebral Small Vessel Disease and nine patients with male infertility, all causal variants were ranked in the top 100 variants with PSAP-genomic-regions. By revisiting the testing units used in the PSAP method to include non-coding variants, we have developed PSAP-genomic-regions, an efficient whole-genome prioritization tool which offers promising results for the diagnosis of unresolved rare diseases.

Recessive loss-of-function variants in DPH1 identified as the molecular cause in a sibling pair previously diagnosed with Fine-Lubinsky syndrome

Fine-Lubinsky syndrome is a rare clinically defined syndrome sometimes referred to as brachycephaly, deafness, cataract, microstomia, and impaired intellectual development syndrome. Here we provide a clinical and molecular update for a sibling pair diagnosed with Fine-Lubinsky syndrome. An extensive genetic work-up, including chromosomal microarray analysis and quad exome sequencing, was nondiagnostic. However, a research reanalysis of their exome sequencing data revealed that both were homozygous for an intronic c.749+39G>A [NM_001383.6] variant in DPH1. RNAseq analysis performed on RNA from fibroblasts revealed significantly reduced expression of DPH1 transcripts suggestive of abnormal splicing followed by nonsense mediated mRNA decay. Since the phenotypes of this sibling pair were consistent with those associated with the inheritance of biallelic pathogenic variants in DPH1, they were given a diagnosis of developmental delay with short stature, dysmorphic facial features, and sparse hair 1 (DEDSSH1). This leads us to recommend that all individuals with a clinical diagnosis of Fine-Lubinsky syndrome be screened for variants in DPH1. The clinical histories of this sibling pair emphasize that hearing loss associated with DEDSSH1 may remit over time and that individuals with DEDSSH1 should be monitored for the development of cardiomyopathy. This case also demonstrates the clinical utility of RNAseq as a means of functionally validating the effects of intronic variants that may affect splicing.

Rare nonsynonymous germline and mosaic de novo variants in Japanese patients with schizophrenia

AIM

Whole-exome sequencing (WES) studies have revealed that germline de novo variants (gDNVs) contribute to the genetic etiology of schizophrenia. However, the contribution of mosaic DNVs (mDNVs) to the risk of schizophrenia remains to be elucidated. In the present study, we systematically investigated the gDNVs and mDMVs that contribute to the genetic etiology of schizophrenia in a Japanese population.

METHODS

We performed deep WES (depth: 460×) of 73 affected offspring and WES (depth: 116×) of 134 parents from 67 families with schizophrenia. Prioritized rare nonsynonymous gDNV and mDNV candidates were validated using Sanger sequencing and ultra-deep targeted amplicon sequencing (depth: 71,375×), respectively. Subsequently, we performed a Gene Ontology analysis of the gDNVs and mDNVs to obtain biological insights. Lastly, we selected DNVs in known risk genes for psychiatric and neurodevelopmental disorders.

RESULTS

We identified 62 gDNVs and 98 mDNVs. The Gene Ontology analysis of mDNVs implicated actin filament and actin cytoskeleton as candidate biological pathways. There were eight DNVs in known risk genes: splice region gDNVs in AKAP11 and CUL1; a frameshift gDNV in SHANK1; a missense gDNV in SRCAP; missense mDNVs in CTNNB1, GRIN2A, and TSC2; and a nonsense mDNV in ZFHX4.

CONCLUSION

Our results suggest the potential contributions of rare nonsynonymous gDNVs and mDNVs to the genetic etiology of schizophrenia. This is the first report of the mDNVs in schizophrenia trios, demonstrating their potential relevance to schizophrenia pathology.

Impaired Wnt/Planar Cell Polarity Signaling in Yellow Nail Syndrome

BACKGROUND

Yellow nail syndrome (YNS) is a rare disorder characterized by a triad of yellow dystrophic nails, lymphedema, and chronic lung disease. Most patients present in adulthood, with only a few congenital or familial cases described. The cause of YNS remains largely unknown, although defects in lymphatic vessel development are suggested to play a significant role.

OBJECTIVE

To elucidate the genetic mechanisms underlying YNS.

DESIGN

Analysis of genetic sequencing data and gene and protein expression studies.

SETTING

A tertiary care academic medical center.

PATIENTS

6 patients with congenital YNS (cYNS) and 5 with sporadic YNS (sYNS).

MEASUREMENTS

Exome and genome sequencing were used to detect disease-causing variants, complemented by RNA analyses for intronic variants. Protein and gene expressions were studied by immunofluorescence staining and real-time reverse transcriptase quantitative polymerase chain reaction analyses.

RESULTS

Biallelic variants in CELSR1 (n = 5) or likely FZD6 (n = 1), both core molecules in the Wnt/planar cell polarity (PCP) pathway, were identified in all patients with cYNS; none of the patients with sYNS had candidate genetic variants. Immunofluorescence staining showed that CELSR1 colocalizes with lymphatic vessels in the skin but not in the lungs or the intestine. Moreover, levels of CELSR1 and FZD6 proteins were negligible to zero in patient tissues (n = 2) compared with control tissues. Gene expression of Wnt/PCP-related genes was reduced in patients with cYNS (n = 3), and patients with sYNS (n = 4) showed milder gene expression impairments.

LIMITATION

Small cohort size and limited sample availability.

CONCLUSION

Defects in PCP organization may play a major role in the pathogenesis of YNS. To the authors' knowledge, this is the first demonstration of a mechanism explaining YNS development, mainly in its congenital form but also in patients with sporadic disease.

PRIMARY FUNDING SOURCE

The Prof. Baum Research Fund of Israel Lung Association.

Comprehensive mapping of genetic variation at Epromoters reveals pleiotropic association with multiple disease traits

There is growing evidence that a wide range of human diseases and physiological traits are influenced by genetic variation of cis-regulatory elements. We and others have shown that a subset of promoter elements, termed Epromoters, also function as enhancer regulators of distal genes. This opens a paradigm in the study of regulatory variants, as single nucleotide polymorphisms (SNPs) within Epromoters might influence the expression of several (distal) genes at the same time, which could disentangle the identification of disease-associated genes. Here, we built a comprehensive resource of human Epromoters using newly generated and publicly available high-throughput reporter assays. We showed that Epromoters display intrinsic and epigenetic features that distinguish them from typical promoters. By integrating Genome-Wide Association Studies (GWAS), expression Quantitative Trait Loci (eQTLs) and 3D chromatin interactions, we found that regulatory variants at Epromoters are concurrently associated with more disease and physiological traits, as compared with typical promoters. To dissect the regulatory impact of Epromoter variants, we evaluated their impact on regulatory activity by analyzing allelic-specific high-throughput reporter assays and provided reliable examples of pleiotropic Epromoters. In summary, our study represents a comprehensive resource of regulatory variants supporting the pleiotropic role of Epromoters.

Genetic variants in PIKFYVE: A review of ocular phenotypes

Many studies have identified disease-causing variants of PIKFYVE in ocular tissues; however, a comprehensive review of these variants and their ocular phenotypes is lacking. The phosphoinositide kinase PIKFYVE plays crucial roles in the endolysosomal pathway in autophagy and phagocytosis, both essential for cellular homeostasis. In this review, we evaluate the reported disease-causing PIKFYVE variants and their associated phenotypes in humans to identify potential genotype-phenotype correlations. Variants in PIKFYVE have been associated with corneal fleck dystrophy, congenital cataracts and possibly keratoconus. There are unvalidated associations of variants in PIKFYVE with autism spectrum disorder and congenital heart disease. We show that variants causing corneal fleck dystrophy exist in the chaperonin-like domain of PIKFYVE as well as the region between the chaperonin-like and the kinase domains. Similarly, congenital cataract variants appear to be specific to the kinase domain of the protein. This review consolidates existing knowledge on PIKFYVE variants in ocular disease and bridges fundamental science and clinical manifestations, potentially informing future diagnostic and treatment strategies for PIKFYVE-associated ocular disorders.

Widening the infantile hypotonia with psychomotor retardation and characteristic Facies-1 Syndrome's clinical and molecular spectrum through NALCN in-silico structural analysis

Introduction

Infantile hypotonia with psychomotor retardation and characteristic facies-1 (IHPRF1, MIM#615419) is a rare, birth onset, autosomal recessive disorder caused by homozygous or compound heterozygous truncating variants in NALCN gene (MIM#611549) resulting in a loss-of-function effect.

Methods

We enrolled a new IHPRF1 patients' cohort in the framework of an international multicentric collaboration study. Using specialized in silico pathogenicity predictors and ad hoc structural analyses, we assessed the mechanistic consequences of the deleterious variants retrieved on NALCN structure and function.

Results

To date 38 different NALCN variants have been retrieved from 33 different families, 26 from unrelated and 22 from related patients. We report on five new IHPRF1 patients from four different families, harboring four newly identified and one previously retrieved variant that exhibited a markedly significant functional impact, thereby compromising the functionality of the protein complex.

Discussion

By widening the functional spectrum of biallelic variants affecting the NALCN gene, this article broadens the IHPRF1 syndrome's genotype-phenotype correlation and gives new insight into its pathogenic mechanism, diagnosis, and clinical management.

Common Variable Immunodeficiency Clinical Manifestations Are Shaped by Presence and Type of Heterozygous NFKB1 Variants

BACKGROUND

NFKB1 encodes p105, which is processed to p50 to mediate canonical nuclear factor-κB (NF-κB) signaling. Although NF-κB is a central driver of inflammation and heterozygous NFKB1 variants are considered the most common monogenic etiologies of common variable immunodeficiency (CVID), few studies have explored how NFKB1 variants shape clinical course or inflammation in CVID.

OBJECTIVE

We leveraged a regional cohort of patients with CVID with and without heterozygous NFKB1 variants to assess how clinical and inflammatory features of CVID are shaped by the presence of these variants.

METHODS

We compared clinical complications, immunologic features, and plasma cytokine levels of 15 patients with CVID with heterozygous NFKB1 variants and 77 genetically undefined patients with CVID from the same referral base. We also assessed differences between patients with CVID with frameshift or nonsense NFKB1 variants compared with those with missense NFKB1 variants.

RESULTS

We found patients with CVID with heterozygous NFKB1 variants to have increased autoimmune disease, bronchiectasis, gastrointestinal infections, inflammatory bowel disease, and plasma cytokines. These findings were more pronounced and included elevation of monocytes in patients with CVID with frameshift or nonsense NFKB1 variants relative to those with missense NFKB1 variants.

CONCLUSIONS

In a regional cohort, heterozygous NFKB1 variants were associated with worsened CVID clinical course and increased evidence of inflammation in the blood. Patients with CVID with frameshift or nonsense NFKB1 variants had more significant increases in noninfectious complications and peripheral monocytes than those with missense NFKB1 variants. Presence of pathogenic NFKB1 variants in patients with CVID may worsen the disease course and warrant closer monitoring.

Alzheimer's Disease Sequencing Project Release 4 Whole Genome Sequencing Dataset

The Alzheimer's Disease Sequencing Project (ADSP) is a national initiative to understand the genetic architecture of Alzheimer's Disease and Related Dementias (AD/ADRD) by sequencing whole genomes of affected participants and age-matched cognitive controls from diverse populations. The Genome Center for Alzheimer's Disease (GCAD) processed whole-genome sequencing data from 36,361 ADSP participants, including 35,014 genetically unique participants of which 45% are from non-European ancestry, across 17 cohorts in 14 countries in this fourth release (R4). This sequencing effort identified 387 million bi-allelic variants, 42 million short insertions/deletions, and 2.2 million structural variants. Annotations and quality control data are available for all variants and samples. Additionally, detailed phenotypes from 15,927 participants across 10 domains are also provided. A linkage disequilibrium panel was created using unrelated AD cases and controls. Researchers can access and analyze the genetic data via NIAGADS Data Sharing Service, the VariXam tool, or NIAGADS GenomicsDB.

Critical Considerations in Calling Disease-Causing EDAR Mutations in Nonsyndromic Oligodontia

Background/Objectives: Oligodontia, the absence of six or more teeth excluding third molars, is a rare genetic condition, unlike hypodontia (missing one or more teeth), which is a relatively common human disease. Methods: To identify the genetic etiology of nonsyndromic oligodontia (NSO) families, we performed mutational analysis and investigated the functional effects of identified EDAR mutations. Whole-exome sequencing was conducted on recruited families with NSO. Bioinformatic analysis identified mutations in oligodontia-causing candidate genes, which were confirmed by Sanger sequencing and segregation within families. The impact of EDAR mutations on the EDA signaling pathway was assessed using luciferase activity analysis. Results:EDAR mutations were identified in three NSO families. A homozygous missense EDAR mutation (NM_022336.4: c.319A>G p.(Met107Val)) was found in the singleton proband of family 1. The proband of family 2 carried compound heterozygous EDAR mutations: a maternal missense mutation (c.319A>G p.(Met107Val)) and a paternal missense variant (c.1270G>A p.(Val424Met)). The proband of family 3 had heterozygous EDAR mutations: a maternal missense mutation (c.389T>A p.(Ile130Asn)) and paternal intronic variants in cis (c.[357-4G>A;440+50C>T]). Luciferase assays confirmed reduced transcriptional activity for all identified missense mutations, while splicing assays revealed altered splicing patterns. Conclusions: In conclusion, recessive EDAR mutations, including novel ones, were identified in NSO families, and their pathological mechanism was explored through transcriptional activity measurements.

Review and metabolomic profiling of unsolved case reveals newly reported autosomal dominant congenital disorder of glycosylation, type Iw formerly thought to only be an autosomal recessive condition

Autosomal dominant congenital disorder of glycosylation (CDG) type Iw (OMIM# 619714) is caused by a heterozygous mutation in the STT3A gene. Most CDGs have an autosomal recessive (AR) mode of inheritance, but several cases with an autosomal dominant (AD) form of an AR CDG have been recently identified. This report describes a 17-year-old male who was referred to the Undiagnosed Diseases Network (UDN) with a history of macrocephaly, failure to thrive, short stature, epilepsy, autism, attention-deficit/hyperactivity disorder, mild developmental delay, intermittent hypotonia, dysmorphic features, and mildly enlarged aortic root. Trio exome sequencing was negative. His biochemical workup included normal plasma amino acids, ammonia, acylcarnitine profile and urine organic and amino acids. His UDN genome sequencing (GS) identified a previously unreported de novo STT3A variant (c.1631A > G: p.Asn544Ser). This variant removes a glycosylation site and was predicted to be destabilizing by structural biology modeling. The patient was formally diagnosed by the UDN Metabolomics Core as having an abnormal transferrin profile indicative of CDG type Iw through metabolomic profiling. We report here an affected male with phenotypic, molecular, and metabolic findings consistent with CDG type Iw due to a heterozygous STT3A variant. This case highlights the importance of further testing of individuals with the phenotypic and metabolic findings of an AR disorder who are heterozygous for a single disease-causing allele and can be shown to have a new AD form of the disorder that represents clinical heterogeneity.

Recurrent eosinophilia with a novel homozygous ARPC1B mutation

Cytoskeletal network dysregulation is a pivotal determinant in various immunodeficiencies and autoinflammatory conditions. This report reviews the significance of actin remodeling in disease pathogenesis, focusing on the Arp2/3 complex and its regulatory subunit actin related protein 2/3 complex subunit 1B (ARPC1B). A spectrum of cellular dysfunctions associated with ARPC1B deficiency, impacting diverse immune cell types, is elucidated. The study presents a patient featuring recurrent and persistent eosinophilia attributed to homozygous ARPC1B mutation alongside concomitant compound heterozygous cystic fibrosis transmembrane conductance regulator (CFTR) gene mutations. We used ARPC1B antibody to stain the patient's peripheral blood lymphocytes and those of the control. The defect in the ARPC1B gene in the present patient caused absent/low expression by immunofluorescence microscopy. The intricate interplay between cytoskeletal defects and immunological manifestations underscores the complexity of disease phenotypes, warranting further exploration for targeted therapeutic strategies.

Spectrum and Prevalence of Rare APOE Variants and Their Association with Familial Dysbetalipoproteinemia

Familial dysbetalipoproteinemia (FD) is a highly atherogenic, prevalent genetically based lipid disorder. About 10% of FD patients have rare APOE variants associated with autosomal dominant FD. However, there are insufficient data on the relationship between rare APOE variants and FD. Genetic data from 4720 subjects were used to identify rare APOE variants and investigate their pathogenicity for autosomal dominant FD. We observed 24 variants in 86 unrelated probands. Most variants were unique (66.7%). Five identified APOE variants (p.Glu63ArgfsTer15, p.Gly145AlafsTer97, p.Lys164SerfsTer87, p.Arg154Cys, and p.Glu230Lys) are causal for autosomal dominant FD. One of them (p.Lys164SerfsTer87) was described for the first time. When we compared clinical data, it was found that carriers of pathogenic or likely pathogenic APOE variants had significantly higher triglyceride levels (median 5.01 mmol/L) than carriers of benign or likely benign variants (median 1.70 mmol/L, p = 0.034) and variants of uncertain significance (median 1.38 mmol/L, p = 0.036). For the first time, we estimated the expected prevalence of causal variants for autosomal dominant FD in the population sample: 0.27% (one in 619). Investigating the spectrum of APOE variants may advance our understanding of the genetic basis of FD and underscore the importance of APOE gene sequencing in patients with lipid metabolism disorders.

Exploring Aerobic Energy Metabolism in Breast Cancer: A Mutational Profile of Glycolysis and Oxidative Phosphorylation

Energy metabolism is a fundamental aspect of the aggressiveness and invasiveness of breast cancer (BC), the neoplasm that most affects women worldwide. Nonetheless, the impact of genetic somatic mutations on glycolysis and oxidative phosphorylation (OXPHOS) genes in BC remains unclear. To fill these gaps, the mutational profiles of 205 screened genes related to glycolysis and OXPHOS in 968 individuals with BC from The Cancer Genome Atlas (TCGA) project were performed. We carried out analyses to characterize the mutational profile of BC, assess the clonality of tumors, identify somatic mutation co-occurrence, and predict the pathogenicity of these alterations. In total, 408 mutations in 132 genes related to the glycolysis and OXPHOS pathways were detected. The PGK1, PC, PCK1, HK1, DONSON, GPD1, NDUFS1, and FOXRED1 genes are also associated with the tumorigenesis process in other types of cancer, as are the genes BRCA1, BRCA2, and HMCN1, which had been previously described as oncogenes in BC, with whom the target genes of this work were associated. Seven mutations were identified and highlighted due to the high pathogenicity, which are present in more than one of our results and are documented in the literature as being correlated with other diseases. These mutations are rs267606829 (FOXRED1), COSV53860306 (HK1), rs201634181 (NDUFS1), rs774052186 (DONSON), rs119103242 (PC), rs1436643226 (PC), and rs104894677 (ETFB). They could be further investigated as potential biomarkers for diagnosis, prognosis, and treatment of BC patients.

A Novel Heterozygous NFKB2 Variant in a Multiplex Family with Common Variable Immune Deficiency and Autoantibodies Against Type I IFNs

We studied a family with three male individuals across two generations affected by common variable immune deficiency (CVID). We identified a novel missense heterozygous variant (c.2602T>A:p.Y868N) of NFKB2 in all patients and not in healthy relatives. Functional studies of the mutant allele in an overexpression system and of the patients' cells confirmed the deleteriousness of the NFKB2 variant and genotype, respectively, on the activation of the non-canonical NF-κB signaling pathway. Impaired processing of p100 into p52 underlies p100 accumulation, which results in gain-of-function (GOF) of IκBδ inhibitory activity and loss-of-function (LOF) of p52 transcriptional activity. The three patients' plasma contained autoantibodies that neutralized IFN-α2 and/or IFN-ω, accounting for the severe or recurrent viral diseases of the patients, including influenza pneumonia in one sibling, and severe COVID-19 and recurrent herpes labialis in another. Our results confirm that NFKB2 alleles that are IκBδ GOF and p52 LOF can underlie CVID and drive the production of autoantibodies neutralizing type I IFNs, thereby predisposing to severe viral diseases.

Analysis of damaging non-synonymous SNPs in GPx1 gene associated with the progression of diverse cancers through a comprehensive in silico approach

Glutathione Peroxidase 1 (GPx1) gene has been reported for its role in cellular redox homeostasis, and the dysregulation of its expression is linked with the progression of diverse cancers. Non-synonymous single nucleotide polymorphism (nsSNPs) have been emerged as the crucial factors, playing their role in GPx1 overexpression. To understand the deleterious mutational effects on the structure and function of GPx1 enzyme, we delved deeper into the exploration of possibly damaging nsSNPs using in-silico based approaches. Eight widely utilized computational tools were employed to roughly shortlist the deleterious nsSNPs. Their damaging effects on structure and function of the genes were evaluated by using different bioinformatics tools. Subsequently, the three final proposed deleterious mutants including mutations rs373838463, rs2107818892, and rs763687242, were docked with their reported binder, TNF receptor-associated factor 2 (TRAF2). The lowest binding affinity and stability of the docked mutant complexes as compared to the wild type GPx1 were validated by molecular dynamic simulation. Finally, the comparison of RMSD, RMSF, RoG and hydrogen bond analyses between wild-type and mutant's complexes validated the deleterious effects of proposed nsSNPs. This study successfully identified and verified the possibly damaging nsSNPs in GPx1 enzyme, which may be linked the progression of various types of cancer. Our findings underscore the value of in-silico approaches in mutational analysis and encourage further preclinical and clinical trials.

Kv3.3 Expression Enhanced by a Novel Variant in the Kozak Sequence of KCNC3

Pathogenic variants in KCNC3, which encodes the voltage-gated potassium channel Kv3.3, are associated with spinocerebellar ataxia type 13. SCA13 is a neurodegenerative disease characterized by ataxia, dysarthria and oculomotor dysfunction, often in combination with other signs and symptoms such as cognitive impairment. Known disease-causing variants are localized in the protein coding regions and predominantly in the transmembrane and voltage sensing domains. In a patient with an ataxic movement disorder and progressive cognitive decline, the c.-6C>A variant was detected in the Kozak sequence of KCNC3. The Kozak sequence is responsible for efficient initiation of translation. Functional analysis of the new c.-6C>A variant and the upstream 5'-UTR region of KCNC3 by luciferase assays, quantitative PCR and methylation analysis shows increased protein expression but no effect on transcription rate. Therefore, increased translation initiation of KCNC3 transcripts compared to wild-type Kozak sequence seems to be the cause of the increased expression. Variants in the regulatory elements of disease-causing genes probably play an underestimated role.

Genetic variants in canonical Wnt signaling pathway associated with pediatric immune thrombocytopenia

ABSTRACT

Through the use of genetic sequencing, molecular variants driving autoimmunity are increasingly identified in patients with chronic and refractory immune cytopenias. With the goal of discovering genetic variants that predispose to pediatric immune thrombocytopenia (ITP) or increase risk for chronic disease, we conducted a genome-wide association study in a large multi-institutional cohort of pediatric patients with ITP. A total of 591 patients were genotyped using an Illumina Global Screening Array BeadChip. Six variants met genome-wide significance in comparison between children with ITP and a cohort of healthy children. One variant in NAV2 was inversely associated with ITP (adjusted odds ratio [aOR], 0.52; P = 3.2 × 10-11). Two other variants in close proximity to NKD1 were also inversely associated with ITP (aOR, 0.43; P = 8.86 × 10-15; aOR, 0.48; P = 1.84 × 10-16). These genes have been linked to the canonical Wnt signaling pathway. No variants met genome-wide significance in comparison of those with ITP that self-resolved in <1 year versus those who developed chronic ITP. This study identifies genetic variants that may contribute to ITP risk and raises a novel pathway with a potential role in ITP pathogenesis.

An abdominal obesity missense variant in the adipocyte thermogenesis gene TBX15 is implicated in adaptation to cold in Finns

Mechanisms of abdominal obesity GWAS variants have remained largely unknown. To elucidate these mechanisms, we leveraged subcutaneous adipose tissue (SAT) single nucleus RNA-sequencing and genomics data. After discovering that heritability of abdominal obesity is enriched in adipocytes, we focused on a SAT unique adipocyte marker gene, the transcription factor TBX15, and its abdominal obesity-associated deleterious missense variant, rs10494217. The allele frequency of rs10494217 revealed a north-to-south decreasing gradient, with consistent significant FST values observed for 25 different populations when compared to Finns, a population with a history of genetic isolation. Given the role of Tbx15 in mouse thermogenesis, the frequency may have increased as an adaptation to cold in Finns. Our selection analysis provided significant evidence of selection for the abdominal obesity risk allele T of rs10494217 in Finns, with a north-to-south decreasing trend in other populations, and demonstrated that latitude significantly predicts the allele frequency. We also discovered that the risk allele status significantly affects SAT adipocyte expression of multiple adipocyte marker genes in trans in two cohorts. Two of these trans genes have been connected to thermogenesis, supporting the thermogenic effect of the TBX15 missense variant as a possible cause of its selection. Adipose expression of one trans gene, a lncRNA, AC002066.1, was strongly associated with adipocyte size, implicating it in metabolically unhealthy adipocyte hypertrophy. In summary, the abdominal obesity variant rs10494217 was selected in Finns, and individuals with the risk allele have trans effects on adipocyte expression of genes relating to thermogenesis and adipocyte hypertrophy.

Multimodal AI/ML for discovering novel biomarkers and predicting disease using multi-omics profiles of patients with cardiovascular diseases

Cardiovascular diseases (CVDs) are complex, multifactorial conditions that require personalized assessment and treatment. Advancements in multi-omics technologies, namely RNA sequencing and whole-genome sequencing, have provided translational researchers with a comprehensive view of the human genome. The efficient synthesis and analysis of this data through integrated approach that characterizes genetic variants alongside expression patterns linked to emerging phenotypes, can reveal novel biomarkers and enable the segmentation of patient populations based on personalized risk factors. In this study, we present a cutting-edge methodology rooted in the integration of traditional bioinformatics, classical statistics, and multimodal machine learning techniques. Our approach has the potential to uncover the intricate mechanisms underlying CVD, enabling patient-specific risk and response profiling. We sourced transcriptomic expression data and single nucleotide polymorphisms (SNPs) from both CVD patients and healthy controls. By integrating these multi-omics datasets with clinical demographic information, we generated patient-specific profiles. Utilizing a robust feature selection approach, we identified a signature of 27 transcriptomic features and SNPs that are effective predictors of CVD. Differential expression analysis, combined with minimum redundancy maximum relevance feature selection, highlighted biomarkers that explain the disease phenotype. This approach prioritizes both biological relevance and efficiency in machine learning. We employed Combination Annotation Dependent Depletion scores and allele frequencies to identify variants with pathogenic characteristics in CVD patients. Classification models trained on this signature demonstrated high-accuracy predictions for CVD. The best performing of these models was an XGBoost classifier optimized via Bayesian hyperparameter tuning, which was able to correctly classify all patients in our test dataset. Using SHapley Additive exPlanations, we created risk assessments for patients, offering further contextualization of these predictions in a clinical setting. Across the cohort, RPL36AP37 and HBA1 were scored as the most important biomarkers for predicting CVDs. A comprehensive literature review revealed that a substantial portion of the diagnostic biomarkers identified have previously been associated with CVD. The framework we propose in this study is unbiased and generalizable to other diseases and disorders.

The Clinical and Genetic Diversity of Thyroid Hormone Resistance: Four Clinical Vignettes

INTRODUCTION

Resistance to thyroid hormones (RTH) is a rare but important genetic cause of decreased peripheral tissue responses to the actions of thyroxine. Most RTH cases are caused by mutations in thyroid hormone receptor β (TRβ, THRB), while a few are caused by mutations in thyroid hormone receptor α (TRα, THRA). RTH is clinically heterogeneous, and the biochemical features are often confusing, resulting in misdiagnoses, mismanagement, and life-long consequences for affected individuals. An awareness of the clinical and genetic spectrum of RTH is therefore essential to avoid misdiagnosis and to ensure timely referral for definitive management.

CASE PRESENTATION

Here we present four clinical vignettes describing three children and one adult with RTH encountered in our "real-world" tertiary pediatric endocrinology practice. We describe a novel THRA (NM_199334.3:c.-298 + 5G>A) missense mutation in the first intron in the 5' untranslated region (UTR) of THRA, with causal variant prediction with Combined Annotation Dependent Depletion placing the mutation in the top 1% most deleterious variants (scaled C-score 21.7). We speculate that this mutation causes an exon skipping event affecting the 5'UTR and protein-coding region, thereby resulting in abnormal or absent TRα1, although supporting clinical, genetic, and/or functional analyses are required to upgrade the pathogenicity classification from uncertain significance to pathogenic/likely pathogenic. The three cases describing "classical" RTH caused by THRB mutations showcase the consequences of misdiagnosis, with 2 patients prescribed medications that could exacerbate symptoms and one child presenting with behavioral problems that might benefit from tailored management with hormone therapies.

CONCLUSION

This report not only highlights the importance of a high index of suspicion for RTH to prompt the genetic diagnosis but also contributes to a growing appreciation of the pathogenic role of non-coding variants in rare diseases.

Mutational scanning of CRX classifies clinical variants and reveals biochemical properties of the transcriptional effector domain

The transcription factor (TF) cone-rod homeobox (CRX) is essential for the differentiation and maintenance of photoreceptor cell identity. Several human CRX variants cause degenerative retinopathies, but most are variants of uncertain significance. We performed a deep mutational scan (DMS) of nearly all possible single amino acid substitutions in CRX using a cell-based transcriptional reporter assay, curating a high-confidence list of nearly 2000 variants with altered transcriptional activity. In the structured homeodomain, activity scores closely aligned to a predicted structure and demonstrated position-specific constraints on amino acid substitution. In contrast, the intrinsically disordered transcriptional effector domain displayed a qualitatively different pattern of substitution effects, following compositional constraints without specific residue position requirements in the peptide chain. These compositional constraints were consistent with the acidic exposure model of transcriptional activation. We evaluated the performance of the DMS assay as a clinical variant classification tool using gold-standard classified human variants from ClinVar, identifying pathogenic variants with high specificity and moderate sensitivity. That this performance could be achieved using a synthetic reporter assay in a foreign cell type, even for a highly cell type-specific TF like CRX, suggests that this approach shows promise for DMS of other TFs that function in cell types that are not easily accessible. Together, the results of the CRX DMS identify molecular features of the CRX effector domain and demonstrate utility for integration into the clinical variant classification pipeline.

Expanding families: a pilot study on preconception expanded carrier screening in Bahrain

BACKGROUND

Preconception expanded carrier screening (ECS) is a genetic test that enables the identification of at-risk carriers of recessive disorders by screening for up to hundreds of genes. Next-generation sequencing (NGS) development has paved the way for its integration into ECS. This study aims to identify the carrier genetic status of couples experiencing or anticipating conception challenges through NGS-based ECS and to gain an overview of the rare genetic disorders in a population with increased consanguinity.

METHODS

Thirty couples who presented to the Genetic Disease Clinic between 2015 and 2024 with failed reproductive outcomes or with a positive personal or family history of genetic disorders and underwent ECS were included and retrospectively analyzed.

RESULTS

Fifty-four individuals (90.00%) were found to carry at least one variant of 95 identified genes, totaling 174 variants. Six individuals (10.00%) tested negative for any variant. Seven individuals had one variant (11.67%), 13 had two variants (21.67%), and 34 had 3 or more variants (56.67%). The most common variants identified were of HBA, HBB, CYP21A2, and G6PD genes. Most of the detected variants were unknown or unexpected (n = 143, 82.18%). Eight couples carried two or more variants in common. Consanguinity was reported in 14 couples (46.67%).

CONCLUSIONS

Preconception ECS is crucial for reproductive planning, permitting couples to evaluate their combined genetic risks and make informed decisions, reducing the chance of having children with genetic disorders.

Dissecting the Reduced Penetrance of Putative Loss-of-Function Variants in Population-Scale Biobanks

Loss-of-function variants (LoFs) disrupt the activity of their impacted gene. They are often associated with clinical phenotypes, including autosomal dominant diseases driven by haploinsufficiency. Recent analyses using biobanks have suggested that LoF penetrance for some haploinsufficient disorders may be low, an observation that has important implications for population genomic screening. However, biobanks are also rife with missing data, and the reliability of these findings remains uncertain. Here, we examine the penetrance of putative LoFs (pLoFs) using a cohort of ≈24,000 carriers derived from two population-scale biobanks: the UK Biobank and the All of Us Research Program. We investigate several possible etiologies for reduced pLoF penetrance, including biobank recruitment biases, annotation artifacts, missed diagnoses, and incomplete clinical records. Systematically accounting for these factors increased penetrance, but widespread reduced penetrance remained. Therefore, we hypothesized that other factors must be driving this phenomenon. To test this, we trained machine learning models to identify pLoFs with high penetrance using the genomic features specific to each variant. These models were predictive of penetrance across a range of diseases and ploF types, including those with prior evidence for pathogenicity. This suggests that reduced ploF penetrance is in fact common, and care should be taken when counseling asymptomatic carriers.

Expanding the spectrum of phenotypes for MPDZ: Report of four unrelated families and review of the literature

MPDZ, a gene with diverse functions mediating cell-cell junction interactions, receptor signaling, and binding multivalent scaffold proteins, is associated with a spectrum of clinically heterogeneous phenotypes with biallelic perturbation. Despite its clinical relevance, the mechanistic underpinnings of these variants remain elusive, underscoring the need for extensive case series and functional investigations. In this study, we conducted a systematic review of cases in the literature through two electronic databases following the PRISMA guidelines. We selected nine studies, including 18 patients, with homozygous or compound heterozygous variants in MPDZ and added five patients from four unrelated families with novel MPDZ variants. To evaluate the role of Mpdz on hearing, we analyzed available auditory electrophysiology data from a knockout murine model (Mpdzem1(IMPC)J/em1(IMPC)J) generated by the International Mouse Phenotyping Consortium. Using exome and genome sequencing, we identified three families with compound heterozygous variants, and one family with a homozygous frameshift variant. MPDZ-related disease is clinically heterogenous with hydrocephaly, vision impairment, hearing impairment and cardiovascular disease occurring most frequently. Additionally, we describe two unrelated patients with spasticity, expanding the phenotypic spectrum. Our murine analysis of the Mpdzem1(IMPC)J/em1(IMPC)J allele showed severe hearing impairment. Overall, we expand understanding of MPDZ-related phenotypes and highlight hearing impairment and spasticity among the heterogeneous phenotypes.

A Case of a Patient With MYH2-Associated Myopathy Presenting With a Chief Complaint of Hand Tremor

Background

Postural tremor is an uncommon and often overlooked phenotype in skeletal myopathy, which may lead to diagnostic delays.

Case report

A 21-year-old man presented with adolescent onset postural hand tremor as the initial symptom, followed by mild limb muscle weakness. Neurological examination showed restricted ocular motility without diplopia and myopathic facial appearance. A muscle biopsy showed a decrease in type 2A fibers. Whole-exome sequencing identified two novel compound heterozygous variants in MYH2 gene (NM_017534.6): c.505+2T>C and c.3565 del C. The diagnosis was further validated via bioinformatics analysis and confirmed through familial co-segregation by Sanger sequencing.

Discussion

This report expands the mutational and phenotypic spectrum of MYH2-associated myopathy. We suggest that in the differential diagnosis of tremor, besides common neurogenic causes, myogenic etiology should also be considered.

Highlights

Hand tremor in this case expands the phenotype of MYH2-associated myopathy, enhancing our understanding of tremor origins. It underscores the importance of nuanced clinical assessment and genetic screening in complex tremor disorders.

Familial partial lipodystrophy resulting from loss-of-function PPARγ pathogenic variants: phenotypic, clinical, and genetic features

The PPARG gene encodes a member of a nuclear receptor superfamily known as peroxisome proliferator-activated gamma (PPARγ). PPARγ plays an essential role in adipogenesis, stimulating the differentiation of preadipocytes into adipocytes. Loss-of-function pathogenic variants in PPARG reduce the activity of the PPARγ receptor and can lead to severe metabolic consequences associated with familial partial lipodystrophy type 3 (FPLD3). This review focuses on recent scientific data related to FPLD3, including the role of PPARγ in adipose tissue metabolism and the phenotypic and clinical consequences of loss-of-function variants in the PPARG gene. The clinical features of 41 PPARG pathogenic variants associated with FPLD3 patients were reviewed, highlighting the genetic and clinical heterogeneity observed among 91 patients. Most of them were female, and the average age at the onset and diagnosis of lipoatrophy was 21 years and 33 years, respectively. Considering the metabolic profile, hypertriglyceridemia (91.9% of cases), diabetes (77%), hypertension (59.5%), polycystic ovary syndrome (58.2% of women), and metabolic-dysfunction-associated fatty liver disease (87,5%). We also discuss the current treatment for FPLD3. This review provides new data concerning the genetic and clinical heterogeneity in FPLD3 and highlights the importance of further understanding the genetics of this rare disease.

Severity Ranking of Missense and Frameshift Genetic Variants in SCD1 by In Silico and In Vitro Functional Analysis

BACKGROUND

A considerable proportion of the symptoms associated with excessive dietary intake can be attributed to systemic imbalances in lipid metabolism. The prominent toxicity of saturated fatty acids has been repeatedly demonstrated and sheds light on the protective role of stearoyl-CoA desaturase-1 (SCD1), the key enzyme for fatty acid desaturation. SCD1 protein expression is regulated at the levels of transcription, translation, and degradation. However, the modulating effect of the variability of the human genome must also be taken into account. Therefore, we aimed to ascertain whether natural missense or frameshift mutations in SCD1 (p.H125P, p.M224L, p.A333T, p.R253AfsTer7) could influence the expression, degradation, or function of the enzyme.

METHODS

In silico and in vitro experiments were conducted to comprehensively evaluate the consequences associated with each genetic variation, with the objective of using the results to propose a risk or severity ranking of SCD1 variants.

RESULTS

As anticipated, the p.R253AfsTer7 variant was identified as the most deleterious in structural, functional, and quantitative terms. The p.H125P variant also reduced the desaturation capacity of the enzyme in accordance with the predicted structural alterations and augmented degradation resulting from folding complications. This was aggravated by increased mRNA instability and accompanied by mild endoplasmic reticulum stress induction. The p.A333T protein exhibited an intermediate phenotype, whereas p.M224L showed no deleterious effects and even increased the amount of SCD1.

CONCLUSIONS

In conclusion, the large-scale identification of genetic variations needs to be supplemented with comprehensive functional characterization of these variations to facilitate adequate personalized prevention and treatment of lipid metabolism-related conditions.

Comprehensive Catalog of Variants Potentially Associated with Hidradenitis Suppurativa, Including Newly Identified Variants from a Cohort of 100 Patients

Hidradenitis suppurativa (HS) is a chronic skin disease characterized by painful, recurrent abscesses, nodules, and scarring, primarily in skin folds. The exact causes of HS are multifactorial, involving genetic, hormonal, and environmental factors. It is associated with systemic diseases such as metabolic syndrome and inflammatory bowel disease. Genetic studies have identified mutations in the γ-secretase complex that affect Notch signaling pathways critical for skin cell regulation. Despite its high heritability, most reported HS cases do not follow a simple genetic pattern. In this article, we performed whole-exome sequencing (WES) on a cohort of 100 individuals with HS, and we provide a comprehensive review of the variants known to be described or associated with HS. 91 variants were associated with the γ-secretase complex, and 78 variants were associated with other genes involved in the Notch pathway, keratinization, or immune response. Through this new genetic analysis, we have added ten new variants to the existing catalogs. All variants are available in a .vcf file and are provided as a resource for future studies.

Investigation of Transcription Factor and Cytokine Gene Expression Levels in Helper T Cell Subsets Among Turkish Patients Diagnosed with ICF2 (Novel ZBTB24 gene Variant) and ICF3 (CDCA7 Variant) Syndrome

Immunodeficiency, centromeric region instability, facial anomalies syndrome (ICF), is a rare disease with autosomal recessive inheritance. ICF syndrome. It has been reported that ICF syndrome is caused by mutations in the DNMT3B (ICF1), ZBTB24 (ICF2), CDCA7 (ICF3), and HELLS (ICF4) genes. As a result of literature research, there are no studies on transcription factor and cytokine expressions of helper T cell subsets in ICF syndrome. In the study; Th1 (TBET, STAT1, STAT4), Th2 (GATA3, STAT6), Th17 (RORgt, STAT3), Treg (FoxP3, STAT5) transcription factors and the major cytokines of these cells (Th1; IFNG, Th2; IL4, Th17; IL17A-21-22, Treg; IL10, TGFβ) expressions were aimed to be evaluated by qRT-PCR. Patients (ICF3: three patients; ICF2: two patients), six heterozygous individual and five healthy controls were included in the study. All patients had hypogammaglobulinemia. Except for the CD19 cells of P2 from patients diagnosed with ICF3, the CD3, CD4, CD8, and CD19 cells in the other ICF3 patients were normal. However, the rates of these cells were low in patients with ICF2 syndrome. Factors belonging to patients' Th1, Th17 and Treg cells were significantly lower than the control. Additionally, novel mutation was detected in ZBTB24 gene (c.1121-2 A > T). Our study is the first molecular study on Th cell subsets in patients with ICF syndrome and a new mutation that causes ICF2 syndrome has been identified.

Unveiling the role of IGF1R in autism spectrum disorder: a multi-omics approach to decipher common pathogenic mechanisms in the IGF signaling pathway

Autism spectrum disorder (ASD) is a complex neurodevelopmental condition marked by impairments in social interaction, communication, and repetitive behaviors. Emerging evidence suggests that the insulin-like growth factor (IGF) signaling pathway plays a critical role in ASD pathogenesis; however, the precise pathogenic mechanisms remain elusive. This study utilizes multi-omics approaches to investigate the pathogenic mechanisms of ASD susceptibility genes within the IGF pathway. Whole-exome sequencing (WES) revealed a significant enrichment of rare variants in key IGF signaling components, particularly the IGF receptor 1 (IGF1R), in a cohort of Chinese Han individuals diagnosed with ASD, as well as in ASD patients from the SFARI SPARK WES database. Subsequent single-cell RNA sequencing (scRNA-seq) of cortical tissues from children with ASD demonstrated elevated expression of IGF receptors in parvalbumin (PV) interneurons, suggesting a substantial impact on their development. Notably, IGF1R appears to mediate the effects of IGF2R on these neurons. Additionally, transcriptomic analysis of brain organoids derived from ASD patients indicated a significant association between IGF1R and ASD. Protein-protein interaction (PPI) and gene regulatory network (GRN) analyses further identified ASD susceptibility genes that interact with and regulate IGF1R expression. In conclusion, IGF1R emerges as a central node within the IGF signaling pathway, representing a potential common pathogenic mechanism and therapeutic target for ASD. These findings highlight the need for further investigation into the modulation of this pathway as a strategy for ASD intervention.

Utility of exome sequencing in primary spermatogenic disorders: From research to diagnostics

BACKGROUND

Primary spermatogenic disorders represent a severe form of male infertility whereby sperm production is impaired due to testicular dysfunction, leading to reduced quality or quantity of spermatozoa. Gene-centered research has certainly demonstrated the importance of the genetic factor in the etiology of both poor sperm morphology or motility and reduced sperm count. In the last decade, next-generation sequencing has expanded the research to whole exome which has transformed our understanding of male infertility genetics, but uncertainty persists in its diagnostic yield, especially in large unrelated populations.

OBJECTIVE

To evaluate the utility of exome sequencing in detecting genetic factors contributing to various traits of primary spermatogenic disorders, which is a crucial step before interpreting the diagnostic yield of the platform.

MATERIALS AND METHODS

We manually curated 415 manuscripts and included 19 research studies that predominantly performed whole exome sequencing in cohorts of unrelated cases with primary spermatogenic defects.

RESULTS

The detection rate, defined as the fraction of cases with an identifiable genetic cause, typically remained below 25% for quantitative defects of spermatozoa, whereas improved rates were observed for traits of abnormal sperm morphology/motility and in populations enriched with consanguineous families. Unlike the quantitative defects, the genetic architecture of the qualitative issues of spermatozoa featured a small number of recurrent genes describing a large fraction of studied cases. These observations were also in line with the lower biological complexity of the pathways affected by the reported genes.

DISCUSSION AND CONCLUSIONS

This review demonstrates the variability in detection rates of exome sequencing across semen phenotypes, which may have an impact on the expectations of the diagnostic yield in the clinical setting.

Whole-exome sequencing study of opioid dependence offers novel insights into the contributions of exome variants

Opioid dependence (OD) is epidemic in the United States and it is associated with a variety of adverse health effects. Its estimated heritability is ∼50%, and recent genome-wide association studies have identified more than a dozen common risk variants. However, there are no published studies of rare OD risk variants. In this study, we analyzed whole-exome sequencing data from the Yale-Penn cohort, comprising 2,100 participants of European ancestry (EUR; 1,321 OD cases) and 1,790 of African ancestry (AFR; 864 cases). A novel low-frequency variant (rs746301110) in the RUVBL2 gene was identified in EUR ( p =6.59×10 -10 ). Suggestive associations ( p <1×10 -5 ) were observed in TMCO3 in EUR, in NEIL2 and CFAP44 in AFR, and in FAM210B in the cross-ancestry meta-analysis. Gene-based collapsing tests identified SLC22A10 , TMCO3 , FAM90A1 , DHX58 , CHRND , GLDN , PLAT , H1-4 , COL3A1 , GPHB5 and QPCTL as top genes ( p <1×10 -4 ) with most associations attributable to rare variants and driven by the burden of predicted loss-of-function and missense variants. This study begins to fill the gap in our understanding of the genetic architecture of OD, providing insights into the contribution of rare coding variants and potential targets for future functional studies and drug development.

CDMPred: a tool for predicting cancer driver missense mutations with high-quality passenger mutations

Most computational methods for predicting driver mutations have been trained using positive samples, while negative samples are typically derived from statistical methods or putative samples. The representativeness of these negative samples in capturing the diversity of passenger mutations remains to be determined. To tackle these issues, we curated a balanced dataset comprising driver mutations sourced from the COSMIC database and high-quality passenger mutations obtained from the Cancer Passenger Mutation database. Subsequently, we encoded the distinctive features of these mutations. Utilizing feature correlation analysis, we developed a cancer driver missense mutation predictor called CDMPred employing feature selection through the ensemble learning technique XGBoost. The proposed CDMPred method, utilizing the top 10 features and XGBoost, achieved an area under the receiver operating characteristic curve (AUC) value of 0.83 and 0.80 on the training and independent test sets, respectively. Furthermore, CDMPred demonstrated superior performance compared to existing state-of-the-art methods for cancer-specific and general diseases, as measured by AUC and area under the precision-recall curve. Including high-quality passenger mutations in the training data proves advantageous for CDMPred's prediction performance. We anticipate that CDMPred will be a valuable tool for predicting cancer driver mutations, furthering our understanding of personalized therapy.