Search Results (649)

Background/Objectives: X-linked Alport syndrome (XLAS) arises from pathogenic variants in COL4A5. Truncating variants are generally classified as severe, but whether clinically meaningful heterogeneity exists within this group remains unclear. This study aimed to establish a novel Col4a5 knock-in mouse model based on a clinical variant and to determine whether truncating mutation position influences disease severity. Methods: A de novo COL4A5 frameshift variant, c.2440delG, was identified in a patient with severe early-onset XLAS. A Col4a5-G814fs knock-in mouse was generated by CRISPR/Cas9 on the C57BL/6J inbred mouse strain background and compared with the established Col4a5-G5X nonsense model using survival analysis, serial functional measurements, kidney histopathology, transmission electron microscopy, and RNA sequencing. Results: The Col4a5-G814fs knock-in mouse was successfully generated and showed loss of glomerular α5(IV) collagen chain expression. Compared with G5X mice, G814fs mice exhibited shorter survival (median 141 vs. 161.5 days, p = 0.0004), earlier onset of proteinuria, and more severe kidney functional decline. By 16 weeks, G814fs mice also showed more severe glomerular basement membrane abnormalities and more extensive glomerulosclerosis. RNA sequencing revealed a shared inflammatory gene signature in both models, together with selective upregulation of genes related to the PPAR signaling pathway and fatty acid metabolism in G814fs kidneys. Conclusions: This study reports a novel de novo COL4A5 frameshift variant and establishes the first Col4a5-G814fs knock-in mouse model. Direct comparison with the G5X model shows that distinct truncating COL4A5 mutations can be associated with substantially different disease severity, providing a useful platform for future mechanistic and therapeutic studies in XLAS. Full article

The question of which Scottish surnames constitute a Clan and which do not is hotly contested. It is wrongly felt, especially in the Scots-abroad communities, that Clan is somehow of higher status than “Family” or “House” and/or applies to everyone of Scottish heritage. Opinions and assertions are on a spectrum between two absolutes: (a) “everyone in Scotland is in a Clan, and everyone should wear kilts and tartans”; to (b) “Clans disappeared in the 18th century and there is no point clinging to a Romantic notion with no modern relevance”. Historically, the Clan is a phenomenon of the Gaelic-speaking Highlands and Islands and was not found as a social structure in the Lowlands; the Southern Uplands (Scottish Borders) are a special case. The “everyone” persuasion leads to cultural nonsenses such as Lowland-ancestry Scots abroad forming “Clan” Societies and adopting Highland dress. Scots overseas are looking for an authoritative statement as to whether their surname constitutes a Clan, a family, or some other nomenclature. Yet, there is no official or agreed historically based list of who are Clans and who are not. There is no such list—or a formula by which an answer can be derived. This essay is intended as a step towards that. Also, the non-historical concept of “Septs” is dismissed. Full article

Background/Objectives: Amelogenesis imperfecta (AI) is a heterogeneous group of rare hereditary conditions mainly affecting the quantity and/or quality of tooth enamel. Its phenotypic expression is diverse, as is the mutational spectrum of the AI-causing genes and mutations. Integrins are cell-surface receptors that mediate adhesion between cells and between cells and the extracellular matrix. Among these, mutations in integrin αvβ6 have been shown to cause AI; however, phenotypic variation exists between the knockout mouse model and human cases, as well as among different human AI families. Methods: We recruited AI families and performed mutational analysis using whole exome sequencing. Results: We identified compound heterozygous ITGB6 mutations in two families. In Family 1, a paternally transmitted nonsense mutation (NM_000888.5: c.1060C>T, p.(Gln354*)) and a maternally transmitted missense mutation (NM_000888.5: c.2312A>G, p.(Asn771Ser)) were identified; in Family 2, a paternal missense mutation (NM_000888.5: c.1693T>C, p.(Cys565Arg)) and a maternal frameshift mutation (NM_000888.5: c.2091delC, p.(Asn698Metfs*13)) were identified, each causing AI in the respective proband. Both probands exhibited generalized hypoplastic and hypomineralized AI, but no other extraoral symptoms. Conclusions: This report will not only expand the known mutational spectrum of the ITGB6 gene but also provide evidence for the genotype–phenotype correlations, thereby improving our understanding of the functional role of ITGB6 during amelogenesis. Full article

This paper is the first attempt to interpret the visual ‘construemes’ by the constructivist poet Alexei N. Chicherin, published in the anthology Mena vsekh which appeared in Moscow in1924. ‘Construemes’ can be considered the most enigmatic artifacts of the Russian avant-garde. Although ‘construemes’ can be easily confused with meaningless visual zaum (‘the transrational’), Chicherin’s actions and the very nature of his personality prevent one from interpreting ‘construemes’ as actionist endeavors to scandalize or a ‘play on nonsense’. Analysis of the poet’s treatise Kan-Fun published in Moscow in 1926 required finding the key to deciphering the ‘construemes’, reveals the positivist nature of Chicherin’s visual–phonological exercises. In the treatise, the poet argues for the primacy of the eye and vision. He illustrates synthetic ‘signs’ or ‘pictograms’ with the quotidian example of propaganda posters, capable of influencing millions more effectively than words alone. The study emphasizes the enigmatic nature of the titles of Chicherin’s books, the Nietzschean subtexts of his self-presentation, encrypted allusions to the esoteric and magical tradition of the Tarot, and religious symbolism. Sixteen illustrations help the understanding of Chicherin’s logic behind the creation of his four ‘construemes’, including the most mysterious composition called ‘Raman’ (‘the shortest Kan-Fun Novel in the world’). The structure of this text synthesizes the verbal, visual–graphic, acoustic (phonological symbols) and musical (notes) levels. The article also examines Chicherin’s proven techniques: the appropriation of the sacred dimension and self-presentation as an actor possessing genuine knowledge and capable of competing alone with the entire literary environment. Full article

Background: CD8A-related CD8α deficiency (Immunodeficiency 116) is a rare autosomal recessive primary immunodeficiency disease characterized by absent CD8⁺ T cells and variable sinopulmonary disease. Case Presentation: A seven-year-old boy from a consanguineous family was referred for chronic wet cough and “uncontrolled asthma” despite being prescribed high-dose inhaled corticosteroids and montelukast. He was hospitalized seven times over a two-year period for presumed asthma exacerbations complicated by pneumonia. An examination revealed bilateral crackles without wheezing. Throat culture tested positive for Haemophilus influenzae. CT imaging showed signs of chronic rhinosinusitis (maxillary mucosal thickening) and chronic airway disease with bronchiectatic changes. The patient’s immunoglobulin levels were within normal ranges for his age group. Flow cytometry revealed profound CD8⁺ T-cell lymphopenia (CD8⁺ 0.21%; 11 cells/µL; near-absent after excluding dual-positive cells) with expansion of CD3⁺CD4⁻CD8⁻ T cells (29.5%). CD8A gene sequencing identified a novel homozygous nonsense variant NM_001768.7:c.319C>T (p.Arg107Ter; GRCh38: chr2:86790412G>A), consistent with loss of CD8α and secondary loss of CD8β surface expression. A literature review identified three previously reported symptomatic patients (and two asymptomatic sisters in the first family), all with recurrent respiratory infections and variable structural lung disease. Conclusions: This case highlights CD8A deficiency as a rare mimic of pediatric asthma and expands the genotype spectrum with a truncating CD8A variant. Early lymphocyte immunophenotyping in children with recurrent sinopulmonary infections may prevent delayed diagnosis and progressive airway damage. Full article

Lumpy skin disease virus (LSDV) is a large DNA capripoxvirus that causes LSD, a disease that has major economic impact. Since 1989, several sporadic outbreaks were reported in Israel, with the latest outbreaks in 2012, 2019 and 2023. Although considered genetically stable, LSDV shows a high degree of genetic recombination events and genetic variations. In particular, in-frame nonsense mutations were suggested to act as one of the main evolutionary drivers of outbreaks. Whole-genome sequencing of LSDV isolates from the 2019 and 2023 outbreaks was used for genomic analysis using various bioinformatics tools to characterize the genomic evolution, recombination events and micro-evolutionary forces shaping LSDV in Israel by comparing isolates. Comparative genomic analysis revealed substantial nucleotide substitutions in the 2019 and 2023 isolates relative to the 2012 isolate. Specifically, increased nucleotide mismatches, inter-genic deletion, enhanced APOBEC editing signatures and elevated codon usage. Additionally, numerous mutations were recognized, leading to structural disruptions in specific viral proteins and possible RNA instability. In conclusion, this analysis supports that nucleotide substitutions, codon selection pressure and APOBEC-associated editing had driven local microevolution of LSDV during the years between outbreaks despite the absence of clinical indications and major vaccination campaigns. Furthermore, genomic evidences of recombination events between the 2012 and 2019 isolates suggests that these processes may have contributed to the emergence of the variant identified during the 2023 outbreak. Full article

ZmSIG2A is a nuclear-encoded plastid sigma factor 2A in maize (Zea mays L.) that is essential for plastid gene transcription and chloroplast biogenesis. As a key regulator of chloroplast development and function, ZmSIG2A may also contribute to the coordination of plant growth and environmental adaptation; however, its roles in root development and stress responses remain largely unclear. We compared two ZmSIG2A mutants, eal1-1 (hypomorphic) and ems110 (nonsense). eal1-1 had increased root number and longer roots, while ems110 had normal root number but shorter roots and failed to mature. The zmsig2a^Val480del transcript was upregulated in eal1-1, and the root-promoting effect of OsSIG2A in rice suggests a conserved role in monocot root growth. DAP-seq indicated that zmsig2a^Val480del targets are involved in metabolism, transport, signaling, and antioxidants, with Chr4 peak clustering near multiple LRR-RLKs, suggesting a ZmSIG2A–LRR-RLK module in root development and stress integration. Physiologically, eal1-1 showed increased antioxidant enzyme activities and reduced MDA, indicating enhanced ROS scavenging, while ems110 exhibited decreased enzyme activities and elevated MDA, indicating compromised ROS detoxification. Upstream, Y1H and dual-luciferase assays demonstrated that the Mediator subunit ZmMed31 positively regulates transcription from the ZmSIG2A promoter. Given Mediator’s role in bridging transcription factors and the core transcriptional machinery, ZmMed31 likely links hormone-responsive transcription factors to the ZmSIG2A regulatory network. Collectively, we propose a stress-responsive ZmMed31–ZmSIG2A–LRR-RLK module that underpins maize root development and drought adaptation, offering mechanistic insight and potential targets for stress-resilient breeding. Full article

Background: Duchenne muscular dystrophy (DMD) is a rare, disabling, and life-threatening X-linked recessive disorder caused by mutations in the dystrophin gene. The current standard of care is treatment with corticosteroids, which aim to decrease inflammation-induced muscle damage and delay disease progression. Here, we aim to describe clinical, genetic, and diagnostic characteristics and evaluate current management practices of DMD patients in the Kingdom of Saudi Arabia (KSA). Methods: This was an ambispective (prospective and retrospective) observational multicenter study evaluating characteristics of patients aged 1–14 years with genetically confirmed DMD in the KSA. The variables of interest were demographics, genetic mutations, clinical characteristics, and initial management. The relationship between the age at diagnosis, initial management plan (standard of care), and age at initiation of treatment on disease outcomes was also evaluated. Results: A total of 226 patients (181 in the retrospective part and 45 in the prospective part) were enrolled. The most common type of genetic mutation was large deletions (134 patients, 59.3%). The median age of first symptom was 2.7 years (IQR: 2.0–4.6 years) and the median age at diagnosis was 7.0 years (IQR: 4.8–8.5 years). Among these patients, the most common initial symptoms were difficulty in walking (87.7%) and waddling gait (41%). The initial management plan for DMD patients involved medication (75.6%) and physical therapy (71.0%). The most frequently prescribed initial medications were vitamin D (82%) and corticosteroids (62.3%). In total, 6/226 patients (2.6%) received ataluren; they all had identified nonsense mutations. The median age of corticosteroid initiation was 7.1 years (IQR: 5.7–8.7). The median age at loss of ambulation (LoA) was 9.8 years (IQR: 8.0–11.4 years) in the non-treated patients; it was 10.1 years (IQR: 9.3–11.2 years) in the steroid-only group and 10.8 years (10.8, 10.8) in the combined ataluren and steroid treatment group. Discussion: Age of diagnosis and age of treatment initiation is relatively late in the KSA. However, early diagnosis and early treatment onset is associated with better clinical outcomes, mainly a delay in LoA. Therefore, there is an urgent need for raising awareness and enhancing early screening in the KSA. Full article

Background: Genetic causes of growth failure should be suspected in patients born small for gestational age (SGA) who fail to show postnatal catch-up growth, present with severe short stature (SS), and exhibit a poor or absent response to growth hormone (rhGH) therapy. Mutations in the insulin-like growth factor 1 receptor (IGF1R) gene are associated with impaired growth, intrauterine growth restriction (IUGR), low birth weight and/or length, and postnatal SS. Case Description: A 9-year-old boy, born SGA for birth length, was evaluated for severe SS. Common causes of SS were excluded. At 9 years and 7 months of age, his height was 112.6 cm (−3.99 SDS), weight 18 kg (−3.79 SDS), and BMI 14.2 kg/m² (−1.8 SDS); pubertal development was Tanner stage 1. The target height was 158 cm (−2.62 SDS). Bone age was delayed by approximately one year compared with chronological age. Serum IGF-1 levels were within the upper-normal range for age. GH therapy (0.035 mg/kg/day) was initiated due to the lack of catch-up growth in an SGA subject. After three years of treatment, the height gain was only 0.5 SDS. IGF-1 levels showed a transient treatment-related increase, followed by persistent normalization during ongoing therapy. Next-generation sequencing (NGS) analysis identified novel heterozygous paternal nonsense variant in the IGF1R gene: c.3498C>G (p.Tyr1166Ter). At 12 years of age, impaired fasting glucose and reduced glucose tolerance were detected; consequently, it was decided to discontinue rhGH therapy, also in light of the IGF1R mutation and the lack of height recovery. Conclusions: This case underlines the critical role of genetic testing in the evaluation of patients born SGA. The coexistence of SGA status and an IGF1R gene mutation may provide a clear explanation for both the poor response to rhGH therapy and the increased risk of alterations in glucose metabolism. An extensive narrative review of the literature on growth outcomes and glucose metabolism abnormalities during GH treatment in SGA patients carrying IGF1R variants was also performed. Full article

Background/Objectives: Coffin–Lowry syndrome (CLS) is a rare X-linked disease caused by pathogenic variants in the RPS6KA3 gene. It is generally characterized by syndromic intellectual disability and distinctive facial features, skeletal abnormalities, stimulus-induced drop attacks in males, and variable manifestations in females. Methods: We report clinical and genetic findings in a series of 10 cases, eight males and two females, evaluated at the Regional Centre of Medical Genetics Dolj—Emergency Clinical County Hospital Craiova. Results: Genetic testing identified 10 de novo variants in the RPS6KA3 gene consisting of six missense mutations, one nonsense variant, one frameshift, and two variants in non-coding or intronic regions. Case management requires multidisciplinary coordination and is limited to resources mostly available in reference centers. Conclusions: CLS highlights the importance of molecular diagnosis in rare genetic disorders, particularly when clinical features are subtle or atypical. These findings have practical implications for clinical management, suggesting the need for comprehensive genetic screening and individualized care approaches. Full article

Introduction: Congenital central hypoventilation syndrome (CCHS) is a rare disorder characterized by an impaired ventilatory response to hypercapnia and hypoxia, particularly during sleep, and frequently associated with autonomic dysfunction. It is caused by pathogenic variants in the PHOX2B gene. Although CCHS is typically diagnosed in the neonatal period, milder forms may present later in infancy or childhood, often triggered by respiratory infections. Case presentation: We report the case of 16-month-old male diagnosed with CCHS following an episode of hypoxemic–hypercapnic respiratory failure during respiratory syncytial virus (RSV) infection. His medical history included neonatal respiratory distress requiring oxygen therapy and recurrent wheezing. At 15 months, he developed acute respiratory distress with severe hypercapnia (PaCO₂ 70 mmHg), requiring admission to the Pediatric Intensive Care Unit and invasive mechanical ventilation. Persistent sleep-related hypercapnia and hypoxemia prompted evaluation for central hypoventilation, confirmed by means of transcutaneous capnography and nocturnal pulse oximetry. Genetic testing revealed a de novo nonsense mutation in exon 1 of PHOX2B (p.Tyr14Ter). Brain magnetic resonance imaging showed diffuse white matter changes suggestive of gliosis. Further investigations identified early-onset systemic hypertension, requiring antihypertensive therapy. The patient was discharged on nocturnal non-invasive ventilation and enrolled in a neurodevelopmental rehabilitation program. Conclusions: This case highlights the phenotypic variability of CCHS and the importance of considering this diagnosis in children presenting with unexplained hypercapnia and sleep-related hypoxemia. It underscores the need for comprehensive autonomic evaluation, including blood pressure monitoring. The p.Tyr14Ter variant may allow partial protein function, potentially accounting for the relatively mild phenotype. Full article

Duchenne muscular dystrophy (DMD) is a severe X-linked neuromuscular disease (NMD) caused by loss-of-function mutations in the DMD gene. RNA-based therapies, especially antisense oligonucleotides (ASO)-mediated exon skipping and adenosine deaminase acting on RNA (ADAR)-guided RNA editing, have emerged as complementary approaches that modulate pre-mRNA splicing or correct transcripts without altering genomic DNA. Current phosphorodiamidate morpholino oligomer (PMO) drugs targeting exons 51, 53, and 45 provide mutation-class-specific benefit. At the same time, next-generation delivery strategies (e.g., peptide-conjugated PMOs (PPMOs), antibody–oligonucleotide conjugates (AOC), and endosomal-escape vehicles) aim to improve skeletal, cardiac, and diaphragm exposure. In parallel, RNA editing strategies offer a route to correct select nonsense or missense variants at the base level and may, in principle, restore near-native dystrophin expression. Meaningful translation of these modalities requires predictive large-animal models. A genome-edited microminipig (MMP) bearing DMD exon-23 mutations faithfully recapitulates hallmark features of human DMD. That includes early locomotor deficits, elevated serum creatine kinase (CK) and cardiac troponin T, progressive myocardial fibrosis, and a decline in left-ventricular ejection fraction (LVEF), while maintaining a manageable lifespan of approximately 30 months suitable for long-term studies. In particular, the MMP model provides a practical platform for addressing the persistent challenge of efficient therapeutic delivery to the heart and diaphragm through longitudinal dosing, imaging, and biopsy. In this review, we synthesize clinical progress in exon skipping, outline the promise of RNA editing, and integrate recent insights from Duchenne muscular dystrophy model for microminipigs (DMD-MMPs) as an advanced surrogate for preclinical development and translational evaluation. Full article

Rapid responses to environmental changes are essential for maintaining fitness. In pathogenic fungi such as the dermatophyte Trichophyton interdigitale, appropriate responses to environmental shifts determine successful infection. Transcriptional regulation and alternative splicing (AS) are key modulators of fungal adaptation and pathogenesis. Here, we validated the role of the transcription factor PacC in coordinating AS in T. interdigitale grown in infection-mimicking medium. RNA-seq analysis of a ΔpacC mutant revealed a predominance of intron retention events, mainly involving introns 1 and 2, indicating defective splicing and potential nonsense-mediated decay of genes related to ion transport, metabolism, and genome maintenance. These alterations compromised energy balance, ergosterol biosynthesis, and cellular homeostasis. PacC-dependent AS generated alternative isoforms of cytoskeletal and metabolic proteins, including myosin-1 and a GH3 β-glucosidase, potentially modulating enzymatic activity, metabolic burden, and cell wall remodeling during infection. Exon-skipping in the chromatin remodeler RSC1 suggests PacC involvement in epigenetic regulation under host-mimicking conditions. Transmission electron microscopy revealed possible Woronin bodies, cytoplasmic disruption, and cell wall thinning in the mutant. Overall, PacC integrates transcriptional and post-transcriptional regulation to promote adaptation, survival, and virulence, highlighting AS as a regulatory layer linking environmental sensing to metabolic and epigenetic plasticity in pathogenic fungi. Full article

Duchenne muscular dystrophy (DMD) is a severe X-linked neuromuscular disorder caused by loss-of-function mutations in the dystrophin gene, leading to progressive muscle degeneration, motor decline, respiratory compromise, and cardiomyopathy. Diagnosis typically occurs in early childhood following recognition of motor delays, markedly elevated creatine kinase, and confirmatory genetic testing. Over the past decade, the therapeutic landscape for DMD has expanded substantially, evolving from exclusively supportive care to patient-centric multifaceted treatment paradigms, including corticosteroids, mutation-specific therapies, small molecule disease-modifying approaches, and gene replacement strategies. Despite these advances, no currently available therapy restores full-length dystrophin or completely halts disease progression. This review provides a clinically oriented comprehensive overview of currently Food and Drug Administration (FDA)-approved medications for DMD, with particular emphasis on corticosteroids, exon-skipping therapies, nonsense mutation readthrough agents, recently approved gene therapy, and select ongoing gene therapy trials. We summarize mechanisms of action, clinical efficacy, safety considerations, regulatory status, and highlight the challenges of integrating these therapies into longitudinal care. Through illustrative clinical vignettes, we highlight the real-world complexity of treatment selection, shared decision-making, and longitudinal care planning in contemporary DMD management. Full article

Background/Objectives: Human induced pluripotent stem cell (hiPSC) models provide a unique platform for testing the effect of genomic variants identified in patients with inherited diseases. In Alström syndrome, a rare multisystem disorder mainly caused by nonsense mutations in the ALMS1 gene, patients often present with infantile cardiomyopathy, retinal dystrophy, type 2 diabetes, and hearing loss in addition to obesity. These diverse clinical manifestations highlight the pleiotropic functions of ALMS1 in cellular processes such as ciliary signalling, cell cycle regulation, and tissue homeostasis. In cats, the ALMS1:c.7384G>C missense variant has been associated with cardiomyopathy in the absence of other symptoms of Alström syndrome, raising questions regarding the impact of this variant on cardiac pathology. Methods: To answer these questions, we generated an hiPSC line carrying the human ALMS1:c.10004G>C missense variant, homologous to the ALMS1:c.7384G>C feline variant, as well as an isogenic control, to investigate the impact of this variant on cardiomyocyte differentiation and function. Results: The introduction of the ALMS1:c.10004G>C variant in the homozygous state in hiPSCs resulted in a significant reduction in cardiomyocyte differentiation efficiency. However, the variant did not affect contractile frequency, sarcomere organisation, sarcomere length, or cardiomyocyte cell size. Together, these results suggest that while the ALMS1:c.10004G>C variant impairs cardiomyocyte differentiation, it does not disrupt the structural or functional properties of the hiPSC-derived cardiomyocytes that do form. Conclusions: We have generated and initiated the characterisation of the third ALMS1 mutant hiPSC line and the first line based on a missense variant, but further research is needed on its relevance in modelling ALMS1-related changes. Our results also support the previous recommendation not to use ALMS1:c.7384G>C for the selection of breeding cats until further data confirm its intrinsic pathogenicity. Full article