Search Results (294)

Background/Objectives: Very early onset inflammatory bowel disease (VEO-IBD), frequently associated with monogenic defects, is increasingly recognized worldwide but remains poorly characterized in Vietnam. This study aimed to characterize the clinical phenotypes and genetic spectrum of Vietnamese children with VEO-IBD. Methods: We conducted a retrospective cohort study at a tertiary pediatric referral center in Vietnam from July 2016 to January 2026. Clinical, laboratory, endoscopic, histopathological, genetic, and treatment data were systematically collected and analyzed. Monogenic variants were identified using next-generation sequencing and classified according to ACMG criteria. Results: Thirty-six children were included, with a median age at onset of 7.5 months, and 72.2% presenting before 24 months. Crohn’s disease predominated (72.2%). Disease burden was high, with growth impairment in 75.0% and anemia in 91.7%. Extraintestinal manifestations were frequent, particularly recurrent infections (72.2%), dermatitis (44.4%), and oral ulcers (44.4%). Perianal disease occurred in 58.3%, with early complications including perianal ulcer (44.4%), perianal abscess (30.6%) and fistulas (33.3%). Inflammatory markers were markedly elevated, and disease activity indices indicated moderate-to-severe disease at diagnosis. Genetic testing was performed in 91.7% of patients, identifying monogenic etiologies in 30.3%. Identified variants involved genes related to immune regulation (IL10RA/IL10RB, FOXP3, XIAP), autoinflammation (TNFAIP3), host defense (CYBB), and epithelial function (MYO5B). Conclusions: Monogenic etiologies account for a substantial proportion of VEO-IBD and are associated with distinct clinical phenotypes and therapeutic implications. Early integration of genomic testing with clinical phenotyping is essential to improve diagnostic precision and enable pathway-based treatment, supporting precision medicine in pediatric IBD. Full article

Neurodegenerative diseases (NDDs) in children represent a heterogeneous group of rare but collectively significant disorders characterized by progressive neurological decline, developmental regression, and substantial morbidity and mortality. Unlike adult-onset neurodegeneration, pediatric conditions are predominantly genetic and frequently arise from defects in fundamental cellular pathways, including lysosomal degradation, mitochondrial oxidative phosphorylation, peroxisomal lipid metabolism, and myelin maintenance. This comprehensive review synthesizes current knowledge regarding the epidemiology, molecular classification, pathophysiology, and emerging therapeutic strategies of major pediatric neurodegenerative disorders. Epidemiological data indicate a “rare-but-many” landscape, where individually uncommon diseases collectively impose a measurable population burden. Mechanistically, disease progression reflects converging processes such as toxic substrate accumulation, impaired autophagy–lysosome flux, mitochondrial bioenergetic failure, oxidative stress, neuroinflammation, and glial dysfunction. Representative groups discussed include lysosomal storage disorders, leukodystrophies, mitochondrial encephalopathies, peroxisomal disorders, and other monogenic neurodegenerative syndromes. Advances in next-generation sequencing, metabolic profiling, and neuroimaging have substantially improved diagnostic accuracy and enabled earlier detection, including through newborn screening programs. Therapeutic paradigms are shifting from primarily supportive care toward mechanism-based interventions, including enzyme replacement therapy, hematopoietic stem cell transplantation, substrate reduction strategies, and gene therapy approaches. Early molecular diagnosis is increasingly recognized as critical for optimizing outcomes, particularly in disorders amenable to presymptomatic intervention. Continued integration of genomic medicine, standardized epidemiologic surveillance, and translational research will be essential to refine disease classification, improve prognostication, and expand access to targeted therapies. Collectively, pediatric neurodegenerative diseases exemplify the intersection of developmental neurobiology and inherited metabolic dysfunction, underscoring the need for multidisciplinary, precision-based clinical strategies. Full article

Monogenic forms of Alzheimer’s Disease (AD) and Frontotemporal Dementia (FTD) represent the two principal neurodegenerative disorders leading to early-onset dementia, primarily linked to mutations in key AD- and FTD-associated genes. The marked heterogeneity in age at onset and penetrance among carriers of pathogenic mutations suggests that monogenic variants act within a broader polygenic background. The combined impact of AD- and FTD-related genetic variation on disease incidence in monogenic forms remains largely unexplored. Herein, we investigate gene–gene interaction patterns in monogenic AD and FTD, with a focus on genetic variability in key AD (APP, PSEN1, PSEN2) and FTD (MAPT, GRN, C9orf72)-associated genes and their association with cumulative disease incidence. Within the GARDENIA Consortium, we studied 426 individuals from Italian pedigrees, including patients (n = 319) and presymptomatic (n = 107) carriers of causative variants in APP (n = 39), PSEN1 (n = 71), PSEN2 (n = 13), MAPT (n = 29), GRN (n = 188), and C9orf72 (n = 86). Age at symptoms onset, age at last follow-up and sex were recorded. Whole exome sequencing was performed, focusing on non-causative variants (n = 64) in the key AD (APP, PSEN1, PSEN2) and FTD genes (MAPT, GRN, C9orf72). Weighted genetic burden scores were derived using Fine–Gray competing risk models to estimate variant-specific effects on cumulative AD and FTD incidence, accounting for mutually exclusive outcomes and family clustering. Model fit was evaluated using Akaike Information Criterion. Higher AD-risk-weighted burden scores in AD-related genes were associated with a significantly increased cumulative incidence of AD, while higher FTD-risk-weighted scores in FTD-related genes showed a trend toward association with increased cumulative incidence of FTD. A significant interaction between burden scores was observed. AD and FTD burden scores showed a negative interaction for AD (~79% attenuation) but a modest synergistic effect for FTD (~6% increase). These findings could imply context-dependent pleiotropy rather than simple additive genetic effects. Our study suggests that even in carriers oh highly penetrant AD or FTD causative variants, genetic background could substantially modulate cumulative disease incidence. Integrating polygenic information with monogenic status may improve prognostic stratification and inform precision approaches in dementia research and clinical trials. Full article

Rice fungal blast, one of the most devastating diseases caused by Magnaporthe oryzae, poses a severe threat to global rice production. For the breeding and deployment of rice varieties with blast resistance, it is critical to elucidate the frequencies and genetic variations in avirulence genes among M. oryzae populations. In this study, a total of 294 M. oryzae isolates were collected in 2022 from central Jilin Province, China. Pathogenicity assays on 24 monogenic rice lines revealed extensive virulence variations among the 294 isolates, with highly pathogenic strains being dominant and clear geographic differences in pathogenicity profiles. Resistance frequencies differed markedly among 24 monogenic lines, with Pi3, Pit, Pi7, Pikh, Pik, and Pia showing resistance rates over 50% and Pish exhibiting the lowest efficacy. Moreover, resistance profiles varied significantly across four sampling regions in central Jilin Province, with Pit being the most effective in Changchun and Jilin, Pi3 in Tonghua, and Pikm in Liaoyuan. In addition, the Avr genotypes of the isolates were postulated based on phenotypic data from the monogenic rice lines. Among the postulated Avr genotypes, the frequencies of Avr-Pi11 and Avr-Pish were the lowest at 29.25%. Furthermore, molecular characterization of three Avr genes (Avr-Pi9, Avr-Pita2, and Avr-Pizt) was performed by sequencing a subsample of 50 randomly selected isolates. Natural mutation sites were identified in Avr-Pita2 and Avr-Pizt, which were located within the coding sequence regions, leading to non-synonymous mutations and nonsense mutations that cause premature termination. Notably, no mutation was detected within the coding sequences of Avr-Pi9. Collectively, the findings provide a theoretical basis for breeding blast-resistant rice varieties that can be deployed in central Jilin Province, China. Full article

Hereditary renal tubulopathies are rare monogenic disorders caused by defects in tubular transport mechanisms that impair the handling of electrolytes, water, and acid–base balance along the nephron. While each tubulopathy is individually uncommon, their collective burden is clinically relevant, as these disorders can severely affect quality of life and predispose to nephrolithiasis, dehydration episodes, and progression to chronic kidney disease. Advances in molecular genetics have identified more than 70 genes involved in renal tubular physiology; however, a substantial proportion of these cases remain genetically unresolved, and marked phenotypic heterogeneity complicates diagnosis and management. This narrative review provides an integrated overview of the main transport systems operating in the different tubular segments of the nephron—proximal tubule, thick ascending limb of the loop of Henle, distal convoluted tubule and collecting duct—summarizing the tubulopathies associated with each segment and discussing in greater detail representative inherited disorders that illustrate the clinical consequences of their dysfunction. We highlight current diagnostic challenges and limitations of existing therapeutic strategies and discuss novel diagnostic approaches as well as emerging treatment options. Improved genetic diagnosis, validation of candidate biomarkers, and the development of novel therapeutic strategies will be essential to advance precision medicine and improve outcomes for patients with inherited renal tubulopathies. Full article

Background: Chronic kidney disease (CKD) in children is frequently associated with underlying genetic etiologies, particularly in cases with early onset, congenital anomalies, or multisystem involvement. The integration of molecular diagnostics into routine nephrological practice represents an important step toward personalized medicine in pediatric CKD. Methods: This retrospective observational study included 50 pediatric patients with CKD stages 2–5 and suspected hereditary etiology evaluated at a tertiary pediatric center. All patients underwent genetic testing using next-generation sequencing and/or chromosomal microarray analysis. Clinical characteristics, CKD stage, extrarenal manifestations, and disease progression were analyzed in relation to genetic findings. Associations between clinical variables and genetic diagnosis were assessed using appropriate statistical tests, including multivariable logistic regression. Results: A positive genetic diagnosis was identified in 28 patients (56%), including 21 monogenic disorders detected by next-generation sequencing and 7 pathogenic copy number variants identified by chromosomal microarray analysis. Extrarenal manifestations were present in 48% of patients and were significantly associated with a higher diagnostic yield (75% vs. 42.3%; OR = 4.09; 95% CI: 1.23–13.61; p = 0.007). Psychomotor delay was strongly associated with pathogenic copy number variants (p < 0.001). Patients with confirmed genetic etiologies exhibited significantly higher rates of CKD progression compared with genetically negative individuals (82.1% vs. 22.7%; OR = 15.64; 95% CI: 3.90–62.7; p < 0.001). In multivariable analysis, genetic diagnosis shows association with disease progression after adjustment for age and baseline renal function. Conclusions: Genetic testing provided a molecular diagnosis in more than half of children with CKD and suspected hereditary etiology. Extrarenal manifestations were strongly associated with a higher diagnostic yield, while confirmed genetic etiologies may be associated with CKD progression. These findings support the early integration of genetic diagnostics into the evaluation of pediatric CKD to improve prognostic assessment and enable more personalized management strategies. Full article

Nephrocalcinosis, defined as the deposition of calcium salts within the renal parenchyma, represents a radiologic and pathologic endpoint shared by a broad spectrum of metabolic and monogenic disorders. Advances in genomic medicine have identified more than 30 genes involved in tubular transport, mineral and acid–base homeostasis, oxalate metabolism, mitochondrial function, ciliary signaling, and nephron development, reframing nephrocalcinosis as a heterogeneous manifestation of discrete molecular defects rather than a single disease entity. Despite this diversity, these conditions converge on common physicochemical pathways of tubular supersaturation, crystal nucleation, growth, and intrarenal retention. These processes are amplified by the intrinsic vulnerability of the renal medulla—characterized by hyperosmolality, hypoxia, and slow tubular flow—and by epithelial injury, loss of crystallization inhibitors, and impaired ciliary signaling. Distinct genotype–phenotype signatures, including age at onset, biochemical profiles, and extrarenal manifestations, provide important diagnostic clues and help differentiate major monogenic entities. The increasing availability of targeted gene panels, whole-exome sequencing, and whole-genome sequencing has substantially improved diagnostic yield, particularly in pediatric populations. Molecular diagnosis now directly informs therapeutic decision-making and long-term management, enabling a shift toward precision nephrology. This narrative review integrates genetic, mechanistic, and clinical perspectives to illustrate how molecular diagnosis reshapes the evaluation, prognosis, and treatment of nephrocalcinosis. Full article

Obesity is characterized by an excess accumulation of adipose tissue, independent of its distribution or function, and is associated with organ dysfunction and a broad range of metabolic and cardiac complications. Nutritional, environmental, behavioral, genetic, psychological, and metabolic factors contribute to obesity. It is associated with many secondary complications, including diabetes mellitus, hypertension, dyslipidemia, metabolic dysfunction-associated steatotic liver disease, reduced quality of life, and psychological illnesses. For practical purposes, childhood obesity can be classified into polygenic, monogenic, syndromic, and endocrine causes. Management should be patient-centered and multidisciplinary, integrating lifestyle/behavioral changes with adjunctive pharmacotherapy and bariatric surgery where appropriate. In monogenic or syndromic obesity, knowing the underlying genetic etiology allows precision-guided and more effective therapy. This review aims to provide a state-of-the-art review on the management of obesity in children. Full article

Background/Objectives: Infantile cardiomyopathy is a rare but often life-threatening condition in which monogenic causes are particularly relevant, especially when cardiac disease is preceded by hypotonia or multisystem involvement. Among sarcomeric genes, MYL2, encoding the ventricular regulatory myosin light chain, plays a critical role in myocardial contractility. However, biallelic MYL2-associated disease remains exceptionally rare, and its clinical spectrum is not fully defined. This study aims to describe a novel case and further delineate the phenotype of recessive MYL2-related cardiomyopathy. Methods: We report a male infant with congenital hypotonia and delayed motor development who underwent extensive metabolic, neuromuscular, and neuroimaging evaluation. Trio-based whole-exome sequencing was performed to identify a potential genetic etiology, followed by variant interpretation using standard bioinformatic and ACMG/AMP criteria. Results: The patient developed acute decompensated heart failure at approximately 10 months of age, with severe left ventricular systolic dysfunction and multiorgan failure, and died at 12 months despite maximal intensive care support. Whole-exome sequencing identified a homozygous MYL2 c.413T>A (p.Met138Lys) missense variant. The variant is absent or extremely rare in population databases, affects a highly conserved residue, is predicted to be deleterious by multiple in silico tools, and is compatible with autosomal recessive inheritance, with both parents confirmed as heterozygous carriers. In the context of a phenotype consistent with recessive MYL2-associated disease, these findings support a likely pathogenic interpretation. Conclusions: This case expands the allelic and phenotypic spectrum of recessive MYL2-associated cardiomyopathy and highlights the value of early genomic testing in infants with unexplained hypotonia and rapidly progressive cardiac dysfunction. Molecular diagnosis may aid in prognosis, clinical decision-making, and genetic counseling. Full article

Advances in technology have provided a better understanding of the genetic basis of neurodegenerative disorders and their underlying molecular pathophysiology. However, treating these disorders with conventional strategies is a major challenge. The approval of gene targeted therapy for spinal muscular atrophy (SMA) has laid the foundation for developing highly personalized therapies for other neurodegenerative disorders. As intensive research and efforts to advance gene targeted therapies continue, this review provides an overview of viral and non-viral vectors and delivery methods, as well as treatment strategies, including gene addition, replacement, editing, silencing, and splice modulation. Gene targeted approaches and clinical trials for SMA and amyotrophic lateral sclerosis (ALS) have demonstrated success, and additional studies are in progress. The design of efficient clinical trials which facilitate successful translation into clinical practice is of critical importance. Key considerations include the selection of appropriate disease models, understanding the natural history of the disease, and establishing well-defined outcome measures to assess prognosis of the disease and therapeutic efficacy. Finally, the precision of CRISPR-based gene editing offers the potential for one-time corrective therapies for monogenic disorders like SMA and SOD1-ALS. Full article

Background: Hypertrophic cardiomyopathy (HCM) is a common inherited disease and a leading known cause of sudden cardiac arrest in young adults and athletes. While genetic testing has advanced rapidly in the past decade, the yield of genetic testing remains low. The Clinical Genome Resource (ClinGen) initiative has become a leading resource for defining the clinical relevance of genetic variants with expert groups focusing on evaluating the strength of evidence for each HCM implicated gene. With the rise of large biobanks and population databases, genetic discovery has been significantly advanced. However, whether these databases can be used to validate gene–disease associations curated by ClinGen and provide evidence for novel gene–disease associations remains unclear. Objectives: Here, we utilized a publicly available database containing 748,879 individuals across three large biobanks (All of Us, UK biobank, Mass General Brigham biobank). Methods: We tested the association of rare coding variants in each gene in the HCM ClinGen panel with HCM. In total, 38 genes were tested, and Bonferroni correction was applied accordingly. Results: Of the 12 genes with definitive evidence for HCM (e.g., MYBPC3, MYH7, TNNT2, ALPK3), 8 (67%) demonstrated nominally significant association with HCM on a population level, and 5 (42%) remained significant after Bonferroni correction, further supporting the validity of these genes in HCM panels. Several definitive genes which are much less commonly affected in HCM (CSRP3, MYL3, ACTC1, TPM1, FHOD3, MYL2, and TNNC1) did not pass our Bonferroni corrected-significance threshold, but all had positively associated effect sizes with HCM. No genes deemed to have moderate or limited evidence had any significant associations with HCM even before Bonferroni correction. Conclusions: Altogether, we show that large biobanks and population databases generally recapitulate established gene–disease associations for HCM and support the ClinGen group’s gene curations. The utilization of such publicly accessible databases represents an additional tool for assessing gene validity in monogenic cardiac disorders with an established phenotype, although it may have limited sensitivity and should not be solely relied on. Full article

Background: Focal segmental glomerulosclerosis (FSGS) is a leading cause of renal disease presenting with steroid-resistant nephrotic syndrome (SNRS) and variable stages of chronic kidney disease (CKD). Monogenic etiologies for FSGS are increasingly recognized, particularly in pediatric and familial cases. Missense variants in the MAF BZIP Transcription Factor B (MAFB) gene cause a dominantly inherited condition with variable phenotype, ranging from isolated ocular or renal manifestations to syndromic FSGS. Methods: Detailed clinical and genetic investigations were conducted in an extended family presenting with a spectrum of renal and extra-renal manifestations. Results: Using Exome Sequencing (ES), a heterozygous variant, c.797T>C; p.(Leu266Pro) in the MAFB gene was identified in multiple affected family members. Variant segregation confirmed its presence in additional family members. The proband exhibited CKD accompanied by congenital auricular anomalies, hearing loss, and neurodevelopmental delay. An affected sibling presented with nephrotic-range proteinuria, Duane retraction syndrome (DRS) and neurodevelopmental involvement, while another family member had an isolated renal phenotype. Several of these features have not been previously associated with MAFB. Tools for structural modeling and stability predictions supported the functional impact of this variant. Conclusions: Our findings expand the phenotypic spectrum of MAFB-associated disease and further emphasize its variability. Full article

Sudden cardiac death (SCD) is a major global health issue, defined as sudden natural death presumed to be of cardiac cause. While in the elderly SCD is commonly associated with coronary artery disease, in the younger population it is linked to inherited cardiomyopathies or channelopathies, even though SCD can remain unexplained even after a comprehensive autopsy in a substantial proportion of cases. In this context, genetic testing has gained importance, supported by the widespread availability of techniques such as next-generation and whole-exome/genome sequencing and their reduced costs. This state-of-the-art review summarizes the genetic bases of sudden cardiac death among cardiomyopathies, channelopathies and in sudden unexplained death presumed to be of arrhythmic cause. Among the structural causes, inherited cardiomyopathies such as hypertrophic, dilated, non-dilated left ventricular, arrhythmogenic right ventricular and restrictive ones represent major substrates for malignant ventricular arrhythmias mostly arising from variants in sarcomeric or desmosomal genes. Channelopathies (long or short QT syndrome, Brugada syndrome and catecholaminergic polymorphic ventricular tachycardia) are caused by variants in genes encoding cardiac ion channels and/or regulatory proteins, which equally predispose to high risk of life-threatening ventricular arrhythmias. In sudden arrhythmic death syndrome, with a structurally normal heart, post-mortem genetic testing (molecular autopsy) can uncover an underlying inherited condition. However, variants of uncertain significance are detected in more than half of the cases, underscoring the need for a multidisciplinary approach. Genetic testing also plays a key role in cascade screening of first-degree relatives. While monogenic variants drive risk in inherited cardiac disorders, emerging evidence suggests that polygenic contributions may modulate SCD susceptibility, highlighting future roles for polygenic risk scores in risk stratification. Full article

Hypertrophic cardiomyopathy (HCM), the most common inherited cardiomyopathy, represents a paradigmatic condition for precision cardiovascular medicine. Once regarded as a monogenic autosomal dominant disorder driven by rare sarcomeric variants, HCM is now recognized as a genetically complex disease characterized by incomplete penetrance, variable expressivity, and heterogeneous clinical trajectories. This review summarizes current evidence on the evolving genetic architecture of HCM, emphasizing the predominant role of definitively validated sarcomeric genes, particularly MYBPC3 and MYH7, and the clinical value of gene panel expansion. Phenotypic variability reflects interactions among variant classes, gene-specific mechanisms, and modifying factors. Differences between missense and truncating variants, haploinsufficiency and poison-peptide effects, allelic imbalance, and age-dependent penetrance contribute to diverse disease expression. Emerging data further support oligogenic inheritance and polygenic modulation, with genome-wide association studies and polygenic risk scores elucidating their contribution to disease susceptibility and variability, especially in genotype-negative patients and carriers of rare variants. We also address genes with emerging evidence and underrecognized pathogenic mechanisms, including deep intronic and splice-altering variants that may explain part of the missing heritability. The importance of distinguishing phenocopies is highlighted, advocating for phenotype-anchored diagnostic pathways integrating clinical assessment, multimodality imaging, and targeted genetic testing. Overall, contemporary data support a targeted, gene-validity-driven approach to genetic testing, where molecular findings primarily inform diagnosis and cascade screening, while risk stratification remains phenotype-led and longitudinal. Future progress will depend on integrative models combining rare variants, polygenic background, imaging, and biomarkers to translate genetic complexity into actionable precision care. Full article

Familial Mediterranean fever (FMF) is a monogenic autoinflammatory disease in which renal involvement is a major determinant of prognosis and is classically dominated by amyloid A (AA) amyloidosis. Non-amyloid renal manifestations are uncommon and poorly characterized. We report a case of clinically overt FMF associated with anti-phospholipase A2 receptor (PLA2R) antibody-positive membranous nephropathy (MN). A 46-year-old man with recurrent febrile episodes fulfilling Tel Hashomer criteria for FMF developed progressive proteinuria with detectable anti-PLA2R antibodies. Genetic testing identified a heterozygous missense MEFV variant in exon 10 (p.Lys695Arg), a mutation with variable penetrance and conflicting pathogenic classification. Kidney biopsy demonstrated PLA2R-positive MN, excluding amyloidosis. After initial conservative management, the patient progressed to nephrotic syndrome complicated by renal vein thrombosis, requiring immunosuppressive therapy according to the Ponticelli regimen in addition to colchicine and anticoagulation, resulting in clinical and immunological remission. In parallel, we performed a systematic review of the literature, identifying only isolated reports of biopsy-proven MN in FMF patients. This case highlights the diagnostic importance of kidney biopsy in FMF patients with proteinuria and illustrates that immune-mediated glomerular disease may occur even in association with non-founder or variably penetrant MEFV mutations, requiring disease-specific management beyond standard autoinflammatory control. Full article