Hypospadias is a common congenital malformation of the male external genitalia, with severe cases presenting considerable surgical and long-term challenges. Despite the clinical importance of severe hypospadias demonstrated by prolonged hospital stays, repeated surgeries, and substantial costs, the genetic etiology of severe hypospadias remains incompletely understood, particularly in diverse populations. To determine the molecular basis, we performed whole-exome sequencing (WES) on 30 Chinese patients from southeastern China with confirmed 46,XY karyotypes. Our analysis identified clinically relevant genetic variants, including single-nucleotide variants (SNVs) and copy number variations (CNVs), with subsequent phenotypic correlation. Clinically relevant genetic variants were identified in 33.3% (10/30) of cases, including novel SNVs in gonadal regulators (nuclear receptor subfamily 5 group A member 1 [NR5A1] c.1344dupC/c.244+1G>T and SRY-box 3 [SOX3] c.1273G>C), morphogenetic modulators (GLI family zinc finger 3 [GLI3] c.4731delA and aristaless-related homeobox [mARX] c.644C>G), and syndromic genes (patched domain containing 1 [PTCHD1] c.667G>A and euchromatic histone lysine methyltransferase 1 [EHMT1] c.3081C>T). Additionally, recurrent CNVs at 22q12.3 and a novel CNV exon 18 deletion in myelin regulatory factor (MYRF) and 18q11.2 were identified. Mutation carriers showed a significantly higher frequency of cryptorchidism (40.0% vs 5.0%, P < 0.01) and a higher prevalence of ≥3 associated malformations (80.0% vs 35.0%, P < 0.05) than non-carriers, highlighting genotype-phenotype correlations. The 33.3% diagnostic yield tripled conventional estimates, demonstrating WES efficacy in identifying SNVs and CNVs in severe phenotypes. These findings reveal the genetic heterogeneity of severe hypospadias and support WES utility in uncovering novel variants and structural genomic alterations.

The plant cytoskeleton is composed of microtubules and actin microfilaments that play instrumental roles in critical processes throughout the cell cycle, including cytokinesis and interphase cell expansion. To facilitate these processes, cytoskeletal polymers are organized into arrays decorated with numerous proteins that modulate array organization and function. Plant genomes contain multiple M icrotubule A ssociated P rotein 65 (MAP65) genes, and only a subset of MAP65’s have been functionally characterized. MAP65 proteins bind and crosslink adjacent microtubules in mitotic, cytokinetic, and interphase arrays in plant cells. The nomenclature used to name different MAP65 genes and subgroups is inconsistent between plant species, which hinders evaluation of MAP65 genes across different species. This review compares and clarifies the MAP65 naming systems to aid the transfer of information across plant species. Proteins in the MAP65–3 group may have a conserved cellular role in organizing the phragmoplast array needed for cytokinesis. Phragmoplasts are disorganized and cytokinesis is incomplete in Arabidopsis thaliana, Cucumis sativus, Oryza sativa, and Zea mays map65–3 loss-of-function mutants. However, the phenotypic severity of map65–3 alleles differs among species. For example, Os MAP65–3 is necessary for rice seedling growth and survival, while cucumber plants lacking Cs MAP65–3 appear wildtype but are less susceptible to Meloidogyne incognita infection. MAP65–1 proteins are involved morphogenesis, cold tolerance, and resistance to specific pathogens in Arabidopsis thaliana, Glycine max, and Solanum lycopersicon . Future studies in model and agricultural plants that better define MAP65 subgroups and evaluate the function of MAP65 proteins in multiple processes could be useful to inform the development of new crop strains.

Type 2 diabetes (T2D) is a heterogenous metabolic condition characterized by varying degrees of insulin resistance and β-cell dysfunction. Preclinical mouse models are essential tools to investigate the mechanisms of T2D pathogenesis and develop therapeutic targets; yet, researchers often fail to specify which aspects of the spectrum of human T2D phenotypes are being modeled. In this mini-review, we critically examine mouse models of T2D and categorize them into recently redefined T2D subtypes according to key pathophysiological features. We focus on models that exhibit (1) insulin deficiency, (2) insulin resistance independent of weight gain, or (3) insulin resistance associated with weight gain. Onset, severity, and progression of metabolic phenotypes are described and discussed in context with clinical presentation in humans. While we find current T2D mouse models do not fully capture the heterogeneity of T2D, strategic model combinations and longer-term phenotyping could help better mimic clinical progression. Existing phenotyping data are often incomplete and largely available only for young male mice. We highlight the urgent need for thorough and standardized phenotyping of both sexes in all models. We also encourage the field to move toward using age-appropriate mice to better reflect human T2D pathophysiology and to advance precision medicine efforts in diabetes research.

This study investigates the clinical course and long-term outcomes of adults with subvalvular aortic stenosis (SAS). Adults with SAS, prospectively registered in the Dutch Congenital Cor Vitia (CONCOR) registry between 2001-2019, were included. All-cause mortality, SAS (re-) operation, and cardiovascular events, including arrhythmias, heart failure, (re-)operation for aortic regurgitation (AR), were assessed. Longitudinal changes in echocardiographic peak velocity, interventricular septal thickness (IVST), and left ventricular posterior wall thickness (LVPW) were analysed using linear mixed-effects models. Differences in the history of SAS repair (operated/unoperated patients), isolated/non-isolated SAS, and sex were explored. Overall, 312 patients were included [age: 26.0 (interquartile range, IQR: 20.0-35.3) years, 68.3% history of SAS repair] with a median follow-up of 16 (IQR: 10-20) years (4423 patient-years). Unadjusted survival at 15 years was lower in the operated group compared to the unoperated group (P = .009) and no significant differences were observed between sexes (P = .083) or isolated/non-isolated SAS (P = .810). The cumulative incidence of (re-)operation for AR at 15 years was 7.6% (95% CI 4.7%-11.0%). The hazard of SAS repair during follow-up was higher in the unoperated group compared to the operated group [HR 0.2 (95% CI 0.1-0.5), P < .001], after correction for covariates. Peak velocity progression was 0.1 m/s (P = .357) during the first period and 0.3 m/s (P = .032) during the second (after ±10 years). No patient showed fast progression (≥0.3 m/s/year) in peak velocity. At baseline no evidence of left ventricular hypertrophy was observed, following IVST/LVPW criteria. Survival of adult SAS patients with a history of SAS repair was substantially lower compared to the unoperated group, reflecting a potentially more severe SAS phenotype. Nevertheless, long-term clinical event rates were considerable. SAS remained stable, suggesting less echocardiographic follow-up may suffice, particularly in mild phenotypes without AR. Additionally, follow-up should focus on the clinical sequelae of SAS.

Retinal detachment (RD) is a sight-threatening emergency requiring urgent intervention to prevent permanent vision loss. While both environmental and genetic risk factors contribute to RD, its complete genetic architecture remains unknown. Here, we performed the largest whole genome sequencing-based case-control study in RD to date, including data from 7,276 RD cases and 236,741 controls in the UK Biobank. Through variant- and gene-level association analyses, we identified VSX2 as a genetic determinant of RD risk while confirming established associations including FAT3, RDH5, and COL2A1. Gene-level collapsing analysis revealed that rare heterozygous missense variants in VSX2 confer a 2.8-fold increased risk of RD (p = 2.4x10-10; odds ratio (OR) = 2.8; 95% confidence interval (CI): [2.1, 3.7]). One missense variant in this gene, p.Glu218Asp, demonstrated a particularly strong effect size (p = 9.3x10-10; OR = 5.9; 95% CI: [3.7, 9.4]). Replication analyses in two additional cohorts, totaling 1,331 cases and 52,355 controls strengthened both the gene- and variant-level associations even further (p = 1.4x10-10 and 1.1x10-11, respectively). Other contributory heterozygous variants included previously reported pathogenic homozygous variants for anophthalmia and microphthalmia. These findings thus reveal a previously unknown gene dosage curve for VSX2, where homozygous mutations cause severe developmental eye disorders and heterozygous mutations cause adult-onset retinal detachment. Extending this observation, we found a significant enrichment for other known recessive Mendelian eye disease genes among nominally significant (p < 0.05) genes associated with RD in the collapsing analysis. This work provides a compelling example of how heterozygous variants in recessive disease genes can be associated with less severe clinical phenotypes.

Vasculopathy and fibrosis are central to the pathogenesis of systemic sclerosis (SSc) and their genetic underpinnings are largely unknown. Here, we sought to examine the aetiology of severe vascular phenotypes and poorer outcomes in African American (AA) patients with SSc. The study focuses on AA patients with SSc who have more severe vascular phenotypes and poorer outcomes and combines genetics, single-cell RNA sequencing, functional assays, and a mouse model to explore the role of NOTCH4 in SSc vasculopathy and the potential for NOTCH4-directed therapies. Gene-based testing identified NOTCH4 association at an exome-wide significance with SSc (P = 1.6 × 10-7) and patients with severe vascular disease (P = 3.5 × 10-7). The risk haplotype defined by the missense (c.2824C>T) and promoter (c.-117G>A) variants was enriched in AAs with SSc (11%) vs controls, and the population attributable risk due to this haplotype in AAs with SSc was 2.6%, which was 52-fold higher than in European Americans. The SSc-associated NOTCH4 variants increased NOTCH4 expression and signalling, leading to decreased angiogenesis and increased endothelial-to-mesenchymal transition (EndoMT). Nailfold capillary abnormalities, decreased angiogenesis, and fibrosis of the vascular lumen are commonly seen in SSc. Genetic, chemical, antibody, or Food and Drug Administration-approved drug inhibition of NOTCH4 signalling rescued angiogenesis and returned EndoMT to baseline. NOTCH4 variants are associated with SSc pathogenesis and vasculopathy, partly explaining the increased prevalence of SSc in AAs. The study highlights the need for further research and clinical trials in the inhibition of the NOTCH4 pathway as a strategy to treat the vascular and fibrotic manifestations of SSc.

Melnick-Needles Syndrome (MNS; OMIM #309350) is a rare X-linked dominant osteochondrodysplasia caused by FLNA gain-of-function variants. It is characterized by short stature, facial dysmorphism, skeletal anomalies, and systemic complications. FLNA encodes Filamin A, a cytoskeletal protein with over 90 binding partners. Variants in FLNA cause a broad spectrum of disorders, among which MNS represents one of the most severe phenotypes. Despite increasing research on MNS, many aspects of its genetic and phenotypic spectrum remain unknown. In this work, we presented two Mexican cases with a diagnosis of MNS with different FLNA missense variants p.(Leu1193Pro) and p.(Ser1199Leu). In addition, we performed a comprehensive review of the literature about FLNA variants related to MNS. This study reinforced the genetic and phenotypic complexity of MNS, emphasizing the critical role of exon 22 variants in the pathogenesis of the disease.

Zebrafish col4a1 loss-of-function models mirror key neurovascular and ocular features of COL4A1/A2 syndrome and enable human variants assessment in vivo.

Pathogenesis of mtDNA point mutation m.10191T>C affecting complex I function is a multifactorial process leading to metabolic remodeling of mitochondria.

Pathogenic variants in the HADHA and HADHB genes are associated with impairment of mitochondrial trifunctional protein. Mitochondrial trifunctional protein deficiency is a disorder of long-chain fatty acid oxidation with different clinical presentations: the neonatal-onset form expressing with severe cardiac phenotype, the infantile-onset form with intermediate hepatic phenotype with metabolic crises, and the late-onset form with mild neuromyopathic phenotype. Long-term complications in patients with the intermediate and late-onset phenotypes include peripheral neuropathy and retinopathy. We report a patient harboring 2 compound heterozygous variants in the HADHA gene (p.Tyr724* and p.Gly319Ser) and presenting with an early-onset, progressive sensorimotor axonal polyneuropathy, without any other systemic manifestations typical of mitochondrial trifunctional protein deficiency. We also provide a literature review of HADHA mutated patients presenting with early-onset isolated neuropathy phenotype.

IgG from anti-MDA5⁺ CADM patients impairs NK cell function via CD16 in RP-ILD.

Impaired PARP1-dependent DNA repair in MORC2 mutations drives axonal degeneration in Charcot-Marie-Tooth disease subtype 2Z and spinal muscular atrophy-like neuromotor disorders.

Endometriosis phenotypes and staging in relation to lipid biomarkers: Findings from the ENDO Cohort Study.

Vici syndrome (VS) is a rare pediatric genetic disorder characterized by profound developmental delay, seizures, immune deficits, cardiomyopathy and progressive motor dysfunction. This devastating condition is caused by pathogenic variants in the EPG5 gene, which encodes a regulator of autophagy, leading to the accumulation of toxic intracellular material and widespread cellular dysfunction. Less-severe EPG5 pathogenic variants have recently been linked to rare familial forms of Parkinson's disease, suggesting deficits in EPG5 function drive a range of neurodegenerative disorders. Currently, there are no effective treatments for any disorders associated with pathogenic variants of EPG5. The underlying cellular mechanisms driving the progressive neurological decline in VS remain poorly understood. Previous studies using Epg5 knockout models have demonstrated severe neurological phenotypes; however, these models have not been characterized for molecular and cellular deficits within the central nervous system. Here we report the generation and analysis of novel genetically engineered mice with mutations in Epg5 as models of VS, including a strain harboring a truncating mutation that recapitulates a patient-derived pathogenic variant and a strain with an Epg5 null allele. These novel Epg5 mutant mouse models exhibited partial perinatal lethality. Neurological deficits of surviving were detectable by 6 weeks of age, and worsen over time. Histological analysis revealed widespread expansion of microglia and astrocytes throughout the central nervous system. Transcriptomic profiling of central nervous system tissue revealed robust neuroinflammatory signatures, sharing molecular profiles with disease-associated microglia observed in other models of neurological disease and injury. The analysis of these novel mouse models of VS suggest a critical role for neuroglial activation in the pathogenesis of VS. These novel in vivo models will be an essential platform for preclinical evaluation of therapeutics that target autophagy-related neurodegeneration in congenital disorders of autophagy and EPG5-associated neurodegeneration.

Autosomal recessive spinocerebellar ataxia-13 is a rare multifactorial disorder characterized by physical disability, cerebellar ataxia, adaptive behavior, intellectual disability, response to sudden noise and light, sensation, skeletal, and oculomotor abnormalities. It affects both males and females equally. So far, only seven variants have been identified in the glutamate metabotropic receptor 1 (GRM1) gene in 18 familial cases of Roma, Iranian, Pakistani, and Tunisian origins. In the present study, we have investigated a large consanguineous family of Pakistani origin presenting severe phenotypes like intellectual disability, delayed developmental milestones, severe ataxia, and nonprogressive neuropathy. Whole exome sequencing was done, followed by Sanger sequencing. Sequence analysis revealed a novel homozygous deletion mutation (c.1715del) in the GRM1 gene (NM_001278064.2) that led to the substitution of Asn with Met at the 572 amino acid position, leading to frame shift and premature termination (p. Asn572MetfsTer4). This study raised the total number of GRM1 variants to eight and would be helpful in prenatal screening, genetic counseling, and carrier testing of other members in the Pakistani community.

Sorting Nexin 27 (SNX27), a key regulator of synaptic receptor trafficking and endosomal recycling, has been implicated in maintaining synaptic homeostasis and cognitive function. To date, variants in SNX27 have been reported in a small number of patients across three publications with severe neurodevelopmental phenotypes. However, the genetic and functional landscape of SNX27-related disorders remains poorly understood, and further evidence is needed to confirm its association with disease and to better delineate the associated phenotype. Two unrelated Pakistani families with a total of five affected individuals segregating a neurodevelopmental disorder were investigated via exome or genome sequencing. This revealed a novel homozygous frameshift variant in family I [NM_001330723.2: c.75dup; p. (Ser26Valfs*85)], predicted to be targeted by nonsense-mediated decay. In family II, a novel homozygous missense variant [NM_001330723.2: c.929 T>C; p. (Met310Thr)] was found within the FERM-like region of the SNX27 protein, which is critical for retromer complex interaction. Comparison of five cases described in this study with previously reported six cases reinforces the presence of consistent "core" clinical features-global developmental delay, intellectual disability, speech delay, behavioral abnormalities, seizures, and motor dysfunction in all assessed cases. Other features such as dental anomalies, failure to thrive, and dysmorphisms occurred variably in few. Affected individuals with predicted loss-of-function variants typically presented with a more severe phenotype. Thus, core features of SNX27-related neurodevelopmental disorders (NDDs) are intellectual disability, developmental, and speech delays. This study, alongside prior reports, augments the genetic and phenotypic spectrum of SNX27-associated NDDs. The novel frameshift variant p.(Ser26Valfs*85) is predicted to severely disrupt SNX27 function, causing profound neurodevelopmental impairment, whereas the missense p.(Met310Thr) in the FERM-like region is associated with a milder phenotype. Comparative analyses with previous reports reveal a spectrum from early lethality to long-term survival with intellectual disability in SNX27-linked families. These findings underscore the importance of SNX27 in neurodevelopment and further validate its link to a neurodevelopmental disorder.

Theory of mind (ToM), the ability of mental state attribution, is an important aspect of social cognition. The autism-psychosis diametrical model suggests that there is an opposite impact of autistic traits and psychotic-like experiences (PLE) upon ToM, with autistic traits associated with under-mentalizing and PLE linked to over-mentalizing. This exploratory study aimed to examine the diametrical model at both subclinical and clinical levels. We recruited 240 college students (Study 1), 28 patients with chronic schizophrenia and their demographically-matched controls (Study 2). The animated shapes task was used to assess ToM ability. This task was a non-verbal task involving the interpretation of geometric figure interactions in random and ToM conditions. All participants completed the Community Assessment of Psychic Experiences (CAPE) and the Autism-Spectrum Quotient (AQ) to measure PLE and autistic traits. The positive symptom subscale (PANSS-P) and the dimensional autism severity score (PAUSS) of the PANSS were additionally used to assess the severity of positive symptoms and autistic phenotypes in clinical populations. Patients with chronic schizophrenia demonstrated a mixed pattern of ToM impairment, combining over-mentalizing for random movements and under-mentalizing for movements involving mental state. Correlational analysis preliminarily suggested that regardless of diagnostic status, PLE was associated with over-mentalizing, that is, more intentionality attribution to random movement. Autistic-like symptoms among patients were related to less intentionality with less appropriate answers in ToM condition. However, the interaction of the two symptoms, or the co-occurrence of PLE and autistic traits had no significant beneficial effect on ToM performances. Autistic traits and positive psychotic symptoms may have differential effects on mentalizing, but there is no support that ToM impairments would be attenuated in individuals with mixed symptom expressions.

Premature ovarian insufficiency (POI) impacts ~1-3.7% of women under the age of 40 globally and is characterised by an absence or complete loss of ovarian function. POI is clinically heterogenous in nature and researchers have identified >100 causative genes harbouring variants responsible for POI thus far. Genes identified to date include those associated with cell differentiation/development, mitochondrial maintenance, hormone receptors, transcription/translation factors, DNA repair/replication, and metabolic processes. Genes encoding cell components that facilitate these processes should therefore also be considered in POI gene candidature. The RNA exosome is a critical component in RNA processing, degradation, and biogenesis in eukaryotic cells. Catalytic activity of the RNA exosome is supplied by two subunits, DIS3 and EXOSC10. Dysregulation of RNA exosome function results in conditions known as exosomopathies that have a broad spectrum of phenotypic severity. RNA transcript regulation is essential in transcriptionally inactive maturing mammalian oocytes with its disruption negatively impacting meiosis and fertilization. Notably, oocyte depletion of Exosc10 significantly impacts the fertility of female mice. Herein we identified, via whole exome sequencing, the first instance of a human POI patient with an EXOSC10 homozygous missense variant. Using Drosophila melanogaster we modelled the impact of knockdown of the EXOSC10 ortholog, Rrp6, on both somatic and germline ovarian cells. We observed that Rrp6 is required in ovarian development in Drosophila. Due to the conserved role of EXOSC10 in fertility maintenance across species we contend that variants in EXOSC10 identified in POI patients may be causative.

BK channels play essential roles in a wealth of physiological functions, including regulating smooth muscle tone and neurotransmitter release. Its dysfunction, often caused by loss-of-function mutations, can lead to severe phenotypes, including ataxia and sensory impairment. Despite the therapeutic potential of BK channel agonists, the molecular mechanisms by which they stabilize the pore's open conformation remain unclear. Using cryoelectron microscopy and molecular dynamic simulations, we identified that NS1619, a synthetic benzimidazolone agonist, first described as a BK opener, binds within a pocket formed by the S6/RCK1 linker and the S4 transmembrane segment. Our simulations suggest that agonist binding promotes a twisting motion in the S6 segment, enabling critical interactions with residues K330, K331, and F223. These findings provide a molecular model for the mechanism of NS1619 and suggest that its binding site can accommodate other agonists, highlighting a promising target for therapeutic development.

BACKGROUNDProgressive familial intrahepatic cholestasis type 3, caused by mutations in the ABCB4 gene, is a rare genetic disorder. Although severe phenotypes due to biallelic mutations are well described, emerging data seem to suggest the clinical relevance of monoallelic variants.AIMTo describe the clinical spectrum and genotype-phenotype correlation of ABCB4 mutations in children in a cohort of North Indian children.METHODSThis is a retrospective analysis of a prospectively maintained database from a single tertiary care centre. Children (≤ 18 years) with ABCB4 mutations between January 2021 and March 2025 were analysed. The clinical presentation, laboratory investigations, genetic sequencing and outcomes were recorded. Patients were stratified into group 1 (homozygous/compound heterozygous) and group 2 (heterozygous). Variant pathogenicity was assessed using the American College of Medical Genetics guidelines and available predictive tools.RESULTSOf the 26 patients, 16 had biallelic mutations, and 10 had monoallelic mutations. Group 1 exhibited higher rates of positive family history (75% vs 30%, P = 0.04), ascites (43.2% vs 0%, P = 0.02), larger varices (40% vs 0%, P = 0.009), higher gamma glutamyl transferase levels (171 U/L vs 38 U/L, P = 0.007), and lower platelet counts (162 × 109/L vs 415 × 109/L, P = 0.007). Notably, two-thirds of patients in group 1 experienced disease progression, and one-third died during follow-up. Certain missense variants (e.g., c.2860T>C) and all nonsense variants were linked to rapid deterioration. Most children in group 2 had transient cholestasis with a good outcome, but two older children succumbed.CONCLUSIONMutations in the ABCB4 gene contribute significantly to pediatric chronic liver disease. Patients with severe biallelic mutations frequently experience a progressive disease course, whereas those with monoallelic mutations may progress slowly. Genetic testing for ABCB4 should be considered in children with cryptogenic chronic liver disease, especially those with high gamma-glutamyltransferase cholestasis and portal hypertension.