Hearing loss is a heterogeneous disorder. Identification of causative mutations is demanding due to genetic heterogeneity. In this study, we investigated the genetic cause of sensorineural hearing loss in patients with severe/profound deafness. After the exclusion of GJB2-GJB6 mutations, we performed whole exome sequencing in 32 unrelated Argentinean families. Mutations were detected in 16 known deafness genes in 20 patients: ACTG1, ADGRV1 (GPR98), CDH23, COL4A3, COL4A5, DFNA5 (GSDDE), EYA4, LARS2, LOXHD1, MITF, MYO6, MYO7A, TECTA, TMPRSS3, USH2A and WSF1. Notably, 11 variants affecting 9 different non-GJB2 genes resulted novel: c.12829C > T, p.(Arg4277*) in ADGRV1; c.337del, p.(Asp109*) and c.3352del, p.(Gly1118Alafs*7) in CDH23; c.3500G > A, p.(Gly1167Glu) in COL4A3; c.1183C > T, p.(Pro395Ser) and c.1759C > T, p.(Pro587Ser) in COL4A5; c.580 + 2 T > C in EYA4; c.1481dup, p.(Leu495Profs*31) in LARS2; c.1939 T > C, p.(Phe647Leu), in MYO6; c.733C > T, p.(Gln245*) in MYO7A and c.242C > G, p.(Ser81*) in TMPRSS3 genes. To predict the effect of these variants, novel protein modeling and protein stability analysis were employed. These results highlight the value of whole exome sequencing to identify candidate variants, as well as bioinformatic strategies to infer their pathogenicity.

Genetic variants in GJB2 and GJB6 genes are the most frequent causes of hereditary hearing loss among several deaf populations worldwide. Molecular diagnosis enables proper genetic counseling and medical prognosis to patients. In this study, we present an update of testing results in a cohort of Argentinean non-syndromic hearing-impaired individuals. A total of 48 different sequence variants were detected in genomic DNA from patients referred to our laboratory. They were manually curated and classified based on the American College of Medical Genetics and Genomics/Association for Molecular Pathology ACMG/AMP standards and hearing-loss-gene-specific criteria of the ClinGen Hearing Loss Expert Panel. More than 50% of sequence variants were reclassified from their previous categorization in ClinVar. These results provide an accurately interpreted set of variants to be taken into account by clinicians and the scientific community, and hence, aid the precise genetic counseling to patients.

Dystrophinopathies are X-linked recessive diseases caused by pathogenic variants in the Duchenne muscular dystrophy (DMD) gene. Some women carrying a single DMD pathogenic variant manifest variable levels of symptomatology. Those who manifest severe and early-onset symptoms are considered to be affected by dystrophinopathy rather than carriers. The aim of this study was to characterize and compare muscle structure between female DMD carriers who were asymptomatic at the time of the study and female control participants using whole-body MRI (WB-MRI) and correlate the findings with clinical and genetic data. We conducted a cross-sectional observational study comparing a group of female carriers of DMD pathogenic variants and a group of healthy noncarrier controls. The first group included obligate and genetically confirmed DMD female carriers, not classified as having dystrophinopathy. Women in the healthy group had no family history of DMD or other muscular dystrophies. All individuals underwent WB-MRI, which was evaluated using qualitative grading scales to assess muscle edema, trophism, and fatty infiltration. Neurologic examinations, serum creatine kinase measurement, DMD genetic screening, and X-chromosome inactivation studies were performed on the DMD carriers. The study included 29 DMD female carriers and 30 healthy noncarrier controls. All DMD carriers showed signs of muscle involvement on MRI, revealing a larger proportion of skeletal muscle involvement in carriers than in controls (85% vs 27% of 48 examined muscles/group of muscles, p < 0.001). Edema, fatty infiltration, and atrophy were more common in DMD carriers (62.5% vs 8%; 81% vs 35%; and 81% vs 25%, respectively, all p < 0.001), particularly in muscles of the calves, thighs, and pelvic region. The most frequently affected muscles were gastrocnemius, gluteus maximus, and soleus. No correlations were found between the MRI results and the clinical and genetic data. Our findings indicate that DMD female carriers who are asymptomatic at the time of our study may be at risk of developing muscle symptoms at a future time. Multidisciplinary surveillance of DMD female carriers will facilitate early detection and management of complications.

Objective: Sarcoglycanopathies are among the most severe limb‐girdle muscular dystrophies (LGMD), though milder presentations have been described. These diseases are primarily caused by missense variants, but the limited predictability of their effect on protein maturation, complex formation, and transport has hindered reliable genotype–phenotype correlations. This study aimed to establish accurate genotype–phenotype correlations for LGMDR3, LGMDR4, and LGMDR5. Methods: We analyzed the largest sarcoglycanopathy cohort to date ( n = 541). Clinical data, including age at symptom onset and loss of ambulation, were collected and used to define phenotype severity. Predictive models were developed considering the impact of non‐truncating variants on secondary structure, functional domains, evolutionary conservation, and intra‐complex protein–protein interactions. Patients carrying two variants predicted to disrupt membrane trafficking were expected to present with severe phenotypes. Results: For LGMDR3, the best‐performing model classified variants affecting β‐sheets, cadherin‐like, and ATP‐binding domains as disruptive to membrane translocation, achieving 89% predictive power, 0.867 balanced accuracy, and 2.4% false‐negative rate (clinically severe patients who were wrongly classified by the model as mild). For LGMDR4 and LGMDR5, the best‐performing model involved conserved residues, β‐sheets, EGF‐like domain, and protein–protein interactions—reaching 80% predictive power, 0.689 balanced accuracy, and 3.1% false‐negative rate (LGMDR4), and 90% predictive power, 0.536 balanced accuracy, with no false negatives (LGMDR5). Additionally, we developed an open‐access predictive tool for clinical and research application. Interpretation: This study provides a robust genotype–phenotype correlation for sarcoglycanopathies, improving prognosis, patient management, and clinical trial recruitment.