Search PubMedSearch

SEARCH · Search PubMed

Results for “monogenic”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 37 records · Page 2Linked to original sources

Genetic background of neurological disorders with basal ganglia calcification.

BACKGROUND: Bilateral basal ganglia calcifications (BGCs), if severe, are known hallmarks for idiopathic BGC disease (IBGC), but if milder, are often considered radiological findings of unknown significance. In previous studies, only a minority of patients with BGC had monogenic forms of IBGC. METHODS: We studied consecutive patients from a tertiary neurology clinic with bilateral BGCs of variable severity, and their families. We analyzed known IBGC genes, and an extended panel of genes linked to monogenic stroke and metabolic conditions. Clinical, radiological, and genetic data were collected, including vascular risk factors, cerebrovascular events, imaging findings (total calcification score, white matter hyperintensities, ischemic/hemorrhagic lesions), and relevant family history. RESULTS: Twenty-four families with BGCs and neurological symptoms were analyzed. Disease-causing variants were identified in 14 families (58.3%). Eight patients had IBGC (variants in SLC20A2, PDGFB, MYORG), 4 had mitochondrial disease (MT-TL1), and 2 had monogenic vascular conditions (GAL, MAP3K6). Three variants were novel. BGC severity was highest in IBGC cases, while vascular and mitochondrial cases had milder calcifications. White matter hyperintensities were seen in 94.7% of cases and correlated highly with the total calcification score. Clinical vascular events had occurred in 41.7% cases. No monogenic cause was found in 10 patients, although many of these showed clinical or radiological features suggestive of monogenic disease. CONCLUSIONS: Bilateral BGCs can occur in many neurogenetic disorders apart from IBGCs, and a broader genetic search increases the diagnostic yield. Patients with BGCs frequently had clinical cerebrovascular events, which emphasizes the role of cerebrovascular pathology in BGCs.

Humans

Role and relevance of genetic testing in patients with kidney stones: a review from EAU Section of Endourology.

PURPOSE OF REVIEW: Kidney stones have a high heritability. More than 40 genes have been identified causing monogenic forms of kidney stone disease (KSD). Kidney stone formers with genetic variants implicated in monogenic forms of KSD often suffer from early onset, high recurrence rates, and chronic kidney disease. Some patients may also exhibit extrarenal disease requiring attention. RECENT FINDINGS: Recent analysis of KSD patients identified a likely monogenic cause in pediatric populations in 17-30% of participants while in adult unselected populations 2.7-8% had a positive finding. More patients carry single genetic variants in monogenic forms that are classically considered as autosomal recessive but may cause an intermediate genetic risk for the development of KSD possibly in interaction with environmental or lifestyle factors. Genome-wide association studies have identified additional risk loci associating with KSD. Their clinical relevance are currently investigated. Patients with recurrent kidney stone episodes may be at elevated risk of progressive chronic kidney disease. SUMMARY: Monogenic causes of KSD are prevalent in patients less than 25 years of age and in some patients with high-risk metabolic profiles. These patients should undergo genetic testing to enable a precise molecular genetic diagnosis and personalized therapy as well as family counseling and screening.

Humans

Obtaining a Diagnostic Yield via Scan findings prior to the introduction of SEquencing retrospectivelY (ODYSSEY): a cohort study.

OBJECTIVE: To determine the retrospective yield of prenatal exome sequencing (PES) by establishing the proportion of children with a postnatal monogenic diagnosis that could have been diagnosed prenatally if PES had been available. METHODS: The study cohort comprised a sample of children in Northern Ireland, born between January 2010 and January 2018 (predating routine availability of PES), who received a monogenic diagnosis postnatally via next generation sequencing as part of either of two UK-wide studies (the 100 000 Genomes Project (2015-2018) or the Deciphering Developmental Disorders study (2011-2015)). Clinical data were collected retrospectively and correlated with the current UK National Health Service PES protocol, including the phenotypic eligibility criteria for PES and the associated fetal anomalies gene panel. Cases were considered retrospective diagnoses if the fetal phenotype would have been eligible for PES and the diagnostic gene was included on the test panel, meaning prenatal diagnosis in this current era could have been feasible. RESULTS: Of 101 children, 17.8% (95% CI, 10.3-25.3%) had both an eligible fetal structural anomaly (FSA) (i.e. high-risk FSA) and a diagnostic gene on the associated test panel, meaning that they could have been diagnosed prenatally in the current clinical landscape. The median length of the diagnostic odyssey for this subgroup of children was 3.7 years (1354 (range, 822-2450) days). Moreover, 58.4% (n = 59) of cases had no anomalies detected prenatally and 19.8% (n = 20) had a FSA that would not meet the eligibility criteria for PES (low-risk FSA). Although these cases would have been ineligible for PES under the current clinical pathway, 89.9% (n = 71/79) were affected by severe or profound syndromes. Postnatally, the most common functional anomalies were neurodevelopmental delay/intellectual disability and/or behavioral abnormality, which were observed in 80.2% (n = 81) of the included children. However, 80.2% (n = 65/81) of these affected children did not present with fetal anomalies eligible for PES. CONCLUSIONS: Almost one-fifth of children with a monogenic condition included in this study could have received a diagnosis via modern PES, avoiding a diagnostic odyssey lasting almost 4 years. However, despite having a monogenic condition, over half of the children did not present with any structural anomalies in utero. This demonstrates the degree to which fetal imaging is limited in its ability to reassure parents of the absence of a fetal genetic syndrome. © 2026 The Author(s). Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Humans

Familial short stature: genetic architecture, risk stratification, and precision management.

BACKGROUND: Familial short stature (FSS) has traditionally been considered a benign growth pattern characterized by short stature clustering within families and has often been regarded as a normal variant of growth. However, recent advances in genomic technologies have demonstrated that a subset of children presenting with an FSS phenotype harbor identifiable monogenic variants, particularly in genes involved in growth plate development and skeletal growth. These findings challenge the traditional phenotype-based understanding of FSS and support an etiology-oriented diagnostic framework. OBJECTIVE: To summarize current knowledge regarding the genetic architecture of FSS, review existing clinical risk stratification frameworks for genetic evaluation, and evaluate available evidence regarding treatment outcomes across different genetic etiologies. METHODS: A literature search was performed in PubMed, Embase, and Web of Science from inception to May 2026, using keywords including "familial short stature," "familial idiopathic short stature," "genetic testing," "ACAN," "SHOX," and "NPR2". Relevant original studies and review articles addressing genotype-phenotype correlations, diagnostic yield of genetic testing, or responses to recombinant human growth hormone (rhGH) therapy were considered. RESULTS: Emerging evidence indicates that monogenic variants can be identified in a subset of children with an FSS phenotype, especially among those with more severe short stature and autosomal dominant inheritance patterns. Variants affecting growth plate biology represent some of the most frequently reported genetic causes of FSS, with ACAN, SHOX, and NPR2 being the most frequently implicated genes. Existing clinical frameworks based on parental height patterns and inheritance characteristics may help stratify patients with FSS according to the likelihood of monogenic etiology and guide selection of individuals who may benefit from genetic testing. Available evidence suggests that rhGH therapy may improve growth outcomes in several monogenic forms of FSS, although treatment responses vary according to genetic etiology. CONCLUSIONS: FSS should be regarded as a heterogeneous clinical phenotype rather than a single diagnostic entity. Integration of existing clinical risk stratification approaches with molecular diagnosis may enable more precise identification of underlying genetic causes and facilitate individualized therapeutic decision-making. Future advances in FSS management will likely depend on precision medicine approaches linking phenotype, genotype, and treatment response.

Humans

Genetic determinants of obesity: mechanisms, clinical implications, and targeted therapies.

PURPOSE: Obesity is a major global health crisis with rising prevalence in both pediatric and adult populations, leading to an increased risk of cardiovascular, metabolic, and other chronic complications affecting all organ systems. A clear understanding of the genetic contributors to polygenic, syndromic, and monogenic obesity is essential for early diagnosis and targeted management. METHODS: Advances in genome-wide association studies (GWAS) and sequencing technologies have greatly expanded our understanding of the genetic alterations underlying this multifaceted disease and have helped in delivering personalized treatment. RESULTS: The pathogenesis of common, polygenic obesity is related to a complex interplay between genetic susceptibility and environmental factors. Syndromic obesity, a less common form, is characterized by early-onset accompanied by additional features such as developmental delay, dysmorphic traits, and various organ system involvement. The rarest form, monogenic obesity, is characterized by severe early-onset non-syndromic obesity caused by mutations in single genes regulating appetite within the hypothalamus. These monogenic obesity cases, though infrequent, have been instrumental in elucidating key pathways involved in hunger and satiety. CONCLUSION: This review provides a comprehensive summary of the most recent findings on the genetic basis of obesity across all age groups, highlighting clinical implications and emerging therapeutic opportunities.

Humans

Pathogenic XPO1 variants cause a dominant neurodevelopmental disorder.

PURPOSE: XPO1 functions in key cellular processes, including nucleo-cytoplasmic export and mitosis. The gene is deleted in a subset of patients with the 2p15p16.1 microdeletion syndrome; however, no monogenic XPO1-related disorder has been described to date. METHODS: We collected clinical data of individuals with de novo XPO1 variants through online matchmaking. We used Drosophila to study XPO1 function in development and habituation learning. RESULTS: A total of 22 individuals met the criteria to be included in the main study cohort. Of these, half have putative loss-of-function variants, and half have coding variants (10 missense and 1 in-frame deletion variant). We found an overlapping phenotype, consistent with a monogenic neurodevelopmental disorder. We demonstrate XPO1 functions in development by ubiquitous and neuron-specific knockdown in Drosophila. GABAergic neuron specific knockdown flies demonstrated impaired habituation. CONCLUSION: Our results establish XPO1 as a novel dominant monogenic neurodevelopmental disorder gene and demonstrate a central role for XPO1 in development.

Exportin 1 Protein

Obesity: exploring its connection to brain function through genetic and genomic perspectives.

Obesity represents an escalating global health burden with profound medical and economic impacts. The conventional perspective on obesity revolves around its classification as a "pure" metabolic disorder, marked by an imbalance between calorie consumption and energy expenditure. Present knowledge, however, recognizes the intricate interaction of rare or frequent genetic factors that favor the development of obesity, together with the emergence of neurodevelopmental and mental abnormalities, phenotypes that are modulated by environmental factors such as lifestyle. Thirty years of human genetic research has unveiled >20 genes, causing severe early-onset monogenic obesity and ~1000 loci associated with common polygenic obesity, most of those expressed in the brain, depicting obesity as a neurological and mental condition. Therefore, obesity's association with brain function should be better recognized. In this context, this review seeks to broaden the current perspective by elucidating the genetic determinants that contribute to both obesity and neurodevelopmental and mental dysfunctions. We conduct a detailed examination of recent genetic findings, correlating them with clinical and behavioral phenotypes associated with obesity. This includes how polygenic obesity, influenced by a myriad of genetic variants, impacts brain regions associated with addiction and reward, differentiating it from monogenic forms. The continuum between non-syndromic and syndromic monogenic obesity, with evidence from neurodevelopmental and cognitive assessments, is also addressed. Current therapeutic approaches that target these genetic mechanisms, yielding improved clinical outcomes and cognitive advantages, are discussed. To sum up, this review corroborates the genetic underpinnings of obesity, affirming its classification as a neurological disorder that may have broader implications for neurodevelopmental and mental conditions. It highlights the promising intersection of genetics, genomics, and neurobiology as a foundation for developing tailored medical approaches to treat obesity and its related neurological aspects.

Humans

Familial pulmonary fibrosis: a UK consensus framework for the investigation and management of patients and their relatives.

Background: There is a growing recognition that genetic predisposition contributes to the development of fibrotic interstitial lung disease. Adult onset monogenic disease is most commonly due to dysfunctional telomere maintenance, with a small proportion caused by surfactant biology disorders. These conditions can be associated with additional intrapulmonary and extrapulmonary features which themselves may require surveillance or treatment, making it important to make a genetic diagnosis. The recent introduction in England of a genetic testing panel accessible to respiratory physicians means that genetic information for these individuals is increasingly available but there is currently little standardisation of the subsequent management of patients and their relatives, which can be complex.Aims: This consensus considers the causes and clinical features of familial pulmonary fibrosis and provides a suggested framework for genetic investigation and clinical management of both patients and their relatives.Narrative: We suggest an initial workup that may help identify those with monogenic disease, with focus on key points in the history and examination that may identify features of a telomere or surfactant biology disorder. We highlight that clinical and radiological presentations are diverse and discuss the importance of making a genetic diagnosis to inform multidisciplinary management and facilitate screening of close family members. We also discuss the many outstanding uncertainties and challenges, including the investigation and management of non-monogenic familial pulmonary fibrosis and the management of asymptomatic family members who have inherited a potentially disease-causing genetic variant.Conclusions: We suggest a pathway for the workup and management of patients with familial pulmonary fibrosis, aiming to standardise clinical care for patients and their relatives and provide a framework for the development of a national database to facilitate disease phenotyping and clinical research to improve the evidence base for clinical practice.

Lung Diseases, Interstitial

Investigating the interplay between prematurity and genetic variation in the context of rare developmental disorders.

BACKGROUND: Rare damaging genetic variation accounts for a substantial proportion of the risk of rare developmental disorders (DDs), but common genetic variants as well as environmental factors, including prematurity, also contribute. Little is known about the interplay between prematurity and genetic variation in influencing phenotypic outcomes in DDs, nor about how genetic factors may contribute to risk of preterm birth in DDs. METHODS: We leveraged phenotypic and genetic data from 21,712 patients with DDs recruited for clinical sequencing, 16% of whom were born prematurely. Using multivariable regression models, we compared phenotypic features and the prevalence of diagnostic genetic variation in specific genes between preterm and term individuals with DDs. We tested whether the fraction of cases attributable to de novo mutations differed between term and preterm probands. Additionally, we assessed whether associations between common variant contributions to education-related traits and prematurity are explained by direct genetic effects. RESULTS: Prematurity was associated with more severe clinical phenotypes among these DD patients, including more affected organ systems and more delayed developmental milestones. Prematurity and the presence of a monogenic diagnosis contributed additively to severity. We found that genes associated with fetal anomalies were enriched for diagnostic mutations among preterm individuals (p = 7.83 × 10-5). We also demonstrated an exome-wide enrichment of de novo mutations (DNMs) in both term and preterm probands; the fraction of cases explained by DNMs in known DD-associated genes was higher in term than preterm cases (25% versus 20%) but DNMs in as-yet-undiscovered genes likely contribute approximately equally to both groups (14% versus 13%). Finally, we showed that the positive association between polygenic predisposition to education-related traits and gestational duration is likely to be the result of genetically influenced parental traits or confounders, rather than direct genetic effects in the child, and that a monogenic diagnosis modifies this association. CONCLUSIONS: Our findings emphasise the importance of considering environmental factors like prematurity in understanding outcomes in DDs suspected to have a genetic component, and motivate further exploration of the role that genetic variation plays in influencing prematurity.

Humans

Extracting and calibrating evidence of variant pathogenicity from population biobank data.

Genomic medicine requires a robust evidence base of variant phenotypic impacts, which remains incomplete even in extensively studied genes with monogenic disease associations. Here, we evaluated the broad potential of using population cohort data to identify evidence that can be used in variant assessment. Across 41 genes related to 18 clinically actionable monogenic phenotypes, we calculated variant-level odds ratios of disease enrichment using data from 469,803 UK Biobank participants. We found significant differences in odds ratio values between ClinVar-labeled pathogenic and benign variants in 11 phenotypes, spanning both common and rare disorders. To facilitate clinical translation, we calibrated the strength of evidence provided by variant-level odds ratios to align with American College of Medical Genetics and Genomics and the Association for Molecular Pathology (ACMG/AMP) interpretation guidelines (PS4 criterion) and found that odds ratios may reach "moderate," "strong," or "very strong" evidence, varying by phenotype and gene. Overall, we found that 2.6% (N = 12,350) of participants harbor a rare variant of uncertain significance (VUS) with at least moderate evidence of pathogenicity-an indication of potentially unrecognized disease risk. Finally, by incorporating computational and functional data alongside population-based odds ratios, we identified variants that met the criteria for clinical reclassification. Notably, using this approach, we identified that 12.4% of rare VUSs in LDLR seen in participants meet diagnostic criteria to be classified as likely pathogenic, demonstrating its potential to scale the reclassification of VUSs.

Humans

An economic evaluation of functional genomic testing for individuals with undiagnosed rare disorders.

PURPOSE: Functional genomics (FG) approaches, such as RNA-seq and proteomics, offer a complementary diagnostic modality for individuals whose cases remain unsolved after genomic sequencing. This study evaluates the cost-effectiveness and cost-benefit of FG for individuals with suspected monogenic disorders relative to manual reanalysis of genomic data at 18 months. METHODS: A decision tree model compared the costs and outcomes of FG and 18-month reanalysis using data from two Australian Undiagnosed Disease Programs. Deterministic and probability sensitivity analysis were performed. RESULTS: With a diagnostic yield of 13%, FG enabled 4 additional diagnoses per 100 individuals tested at an additional cost of $390 (US $240), resulting in an incremental cost-effectiveness ratio of $8,550 ($5,313) and an 85% probability of being cost-effective. CONCLUSION: Functional genomics enables timely diagnosis for individuals with suspected monogenic disorders by evaluating the functional impact of variants of uncertain significance, offering an advantage over reanalyzing genomic data at 18 months. Integration into the Australian healthcare system, supported by collaborative networks and secure data-sharing infrastructure, coupled with addressing barriers to accessing funded genomic testing, could lead to an annual net benefit of up to $1.1 million ($0.7 M).

Functional genomics

Neuropsychiatric disease mechanisms and interventions from 22q11.2 deletion syndrome experimental studies.

A high genetic predisposition for neuropsychiatric disorders, such as schizophrenia and autism spectrum disorders (ASDs), is 22q11.2 deletion syndrome (22q11DS), caused by a hemizygous microdeletion in the q-arm of human chromosome 22. The deletion most often spans a 3 Mb region, with variable breakpoints ranging from 1.5 to 3 Mb. Experimental studies on 22q11DS have revealed several aspects of the pathophysiology of neuropsychiatric disorders and also identified various interventional and rescue strategies. Herein, we review these strategies by grouping the studies into three main mechanistic categories: (i) microRNA (miR)-mediated, (ii) mitochondrial, and (iii) neural circuit deficits in polygenic deletion, and also briefly describe a few other monogenic mechanisms implicated. Haploinsufficiency of Dgcr8, a 22q11DS gene involved in miR processing, forms the center of miR-mediated mechanisms and rescuing consequent pathophysiology rely on age-dependent, brain region-specific or global replenishment of miRs or their targets. Seven genes in the 22q11.2 genomic region encode mitochondrial proteins and approaches to mitigate these gene deficiencies concentrate on the respective mitochondrial functions affected. We briefly describe other potential monogenic mechanisms for intervention including transcriptional regulation, synaptic release, catecholamine metabolism, and cell-cell adhesion, represented by Tbx1, Sept5, Comt, Arvcf, and Cldn5. We also give examples of how the multifaceted pathophysiological mechanisms and rescue strategies can have convergent effects at the molecular, synaptic, cellular and circuit levels. Based on the experimental interventions identified in the 22q11DS studies, we inform on the supportive therapies possible now and the future potential of curative interventions.

Humans

Rare variants and survival of patients with idiopathic pulmonary fibrosis: analysis of a multicentre, observational cohort study with independent validation.

BACKGROUND: Rare pathogenic variants in telomere-related genes are associated with poorer clinical outcomes in idiopathic pulmonary fibrosis (IPF). We aimed to assess whether rare qualifying variants in monogenic adult-onset pulmonary fibrosis genes are associated with IPF survival. Using polygenic risk scores (PRS), we also evaluated the influence of common IPF risk variants in patients carrying the qualifying variants. METHODS: We identified qualifying variants in telomere and non-telomere genes using whole-genome sequences from individuals clinically diagnosed with IPF and enrolled in the Pulmonary Fibrosis Foundation Patient Registry (PFFPR), a large multicentre, observational cohort study (March 29, 2016 to June 15, 2018, n=888). We also derived a PRS for IPF (PRS-IPF) from known common sentinel IPF variants. The primary outcome was the association between qualifying variants and survival. The secondary outcome was the association between qualifying variants and PRS-IPF. We used logistic regression models adjusted for sex, age at diagnosis, and principal components of genetic heterogeneity to examine the mutual relationship of qualifying variants and PRS-IPF. The association between qualifying variants and PRS-IPF with survival was tested using Cox proportional hazard models adjusted for baseline confounders. Validation of the results was sought in data from an independent multicentre, prospective, observational cohort study of IPF in the UK (PROFILE, May 17, 2010 to Sept 5, 2017, n=472), and results were meta-analysed under a fixed-effects model. FINDINGS: We included 888 patients from PFFPR and 472 from PROFILE, totalling 1360 participants. In the PFFPR, carriers of qualifying variants in monogenic adult-onset pulmonary fibrosis genes were associated with lower PRS-IPF (odds ratio 1·79 [95% CI 1·15-2·81]; p=0·010) and shorter survival (hazard ratio 1·53 [1·12-2·10]; p=7·33 × 10-3). Individuals with the lowest PRS-IPF also had worse survival (1·61 [1·25-2·07]; p=1·87 × 10-4). These findings were validated in PROFILE and the meta-analysis of the results showed a consistent direction of effect across both cohorts. INTERPRETATION: We found non-additive effects between qualifying variants and common risk variants in IPF survival, suggesting distinct disease subtypes and raising the possibility of using PRS to guide sequencing prioritisation. Assessing the carrier status for qualifying variants and modelling PRS-IPF promises to further contribute to predicting disease progression among patients with IPF. FUNDING: Instituto de Salud Carlos III; Instituto Tecnológico y de Eenergías Renovables; Cabildo Insular de Tenerife; Fundación DISA; National Heart, Lung, and Blood Institute of the US National Institutes of Health; and UK Medical Research Council.

Humans

Assessing the de novo paradigm in sporadic early-onset Alzheimer disease trios.

The genetic architecture of sporadic Early-Onset Alzheimer Disease (sEOAD, onset ≤65 years) remains largely unknown. To assess the de novo mutation (DNM) hypothesis, we performed a nationwide recruitment of 37 novel sEOAD patients-unaffected parents trios. After assessing known monogenic genes, we performed trio-based exome sequencing and jointly analyzed novel trios with 12 previously reported ones. Of these, we selected 16 trios for genome sequencing. We identified three patients with a pathogenic DNM in APP or PSEN1. Then, from the 46 remaining trios, we identified 38 non-synonymous coding DNM and 4 de novo copy number variants (CNVs) in exome data. Four DNM (2 novel, in SPHK2 and DDR1) and bi-allelic inherited variants in two genes affected Alzheimer disease-related genes. No significant burden of rare coding variants in exome/genome data from 5643 EOAD cases and 16097 controls was identified using nested windows centered on each DNM position, at the transcript level. From genome data, one non-coding DNM was predicted to affect splicing in an AD-associated gene, PINX1. Overall, 48% probands carried ≥1 inherited risk factor with odds ratio (OR) > 1.5 and GWAS-defined Genetic Risk Scores (GRS) distribution was more consistent with random distribution than enrichment in higher scores in probands. We confirm that DNMs in known monogenic genes explain sEOAD in a minority of cases, while candidate DNMs in other genes might account for a small proportion of additional cases. The majority of sEOAD patients may have a complex etiology including multiple inherited variants, however, GRS might not explain most of its genetic component.

Humans

Mechanisms underlying disease-causing variants in promoters and enhancers.

The study of human monogenic disorders has been a powerful tool for generating a deep understanding of protein function/dysfunction and for uncovering underlying biological mechanisms. Here we explore the insights that an expanding catalog of noncoding monogenic disease variants can provide into the functions of the noncoding genome. We focus on small genetic alterations (one to a few tens of base pairs) in cis-regulatory elements-promoters, enhancers and silencers-and their potential mechanisms of action, such as loss or gain of function. We discuss the challenges in determining pathogenicity for variants in the noncoding genome, discuss why there might be so few concrete examples and highlight the opportunities for advancing this area of human genetics by using experimental and machine-learning tools.

Journal Article

Biallelic pathogenic variants in FLNB are associated with paediatric steroid-resistant nephrotic syndrome via podocyte cytoskeletal dysfunction.

BACKGROUND: Steroid-resistant nephrotic syndrome (SRNS) is a severe paediatric kidney disease and a leading cause of end-stage kidney disease in children, with a high genetic contribution. While over 80 monogenic causes of SRNS have been identified, a significant proportion of affected patients still lack a clear genetic diagnosis, indicating that additional causative genes remain to be discovered. METHODS: Through whole-exome sequencing of a paediatric SRNS cohort, we identified three probands carrying biallelic FLNB pathogenic variants. Sanger sequencing was performed for familial cosegregation verification and ACMG classification. Expression of Filamin B, Nephrin and Synaptopodin in renal tissues was assessed by immunohistochemistry/immunofluorescence. Wild-type and patient-derived variant FLNB plasmids were constructed and transfected into HEK293T cells and immortalised human podocytes (HPCs). The effects of these variants on protein expression, localisation and cytoskeletal organisation were assessed by western blotting and immunofluorescence. FLNB expression in HPCs was silenced using shRNA to evaluate the impact on podocyte marker proteins, cytoskeletal integrity and migratory capacity. A zebrafish flnb knockdown model was employed to validate its effects on renal development. RESULTS: All three probands presented with isolated SRNS without skeletal developmental abnormalities, and renal tissues showed significantly reduced Filamin B protein expression. In vitro, p.L117P and p.M1803L variants led to markedly reduced protein expression, while p.R470L and p.K2586R induced perinuclear aggregation of Filamin B accompanied by F-actin rearrangement. FLNB silencing led to downregulation of Nephrin and Synaptopodin, cytoskeletal disorganisation and impaired cell migration. Zebrafish flnb knockdown exhibited pericardial oedema, defective nephron development and abnormal podocyte foot processes. CONCLUSION: We report for the first time that biallelic FLNB pathogenic variants are associated with paediatric SRNS by disrupting Filamin B expression, cytoskeletal integrity and podocyte function, providing evidence that FLNB is a novel monogenic cause of SRNS.

Humans

Integrating Optical Genome Mapping into the Genetic Diagnostic Algorithm: Clinical Utility in Unresolved Autosomal Recessive Disorders from a Large Cohort.

INTRODUCTION: The identification of precise genetic etiologies is indispensable for the clinical management of monogenic disorders. However, conventional diagnostic methods and exome sequencing (ES) frequently fail to identify complex structural variations (SVs), leaving the genetic basis unexplained in approximately 30-60% of suspected cases. Optical genome mapping (OGM) emerges as a high-resolution technology capable of detecting cryptic SVs inaccessible to standard methodologies. METHODS: In this study, we evaluated the clinical utility of integrating OGM into the diagnostic algorithm for unresolved monogenic diseases. Following negative or inconclusive results from standard ES pipelines, OGM was applied to a targeted subset of patients (n = 7) selected from a comprehensive clinical cohort of 1,257 individuals with suspected genetic disorders. RESULTS: The integration of OGM identified candidate SVs that may represent the second allelic alteration in two distinct cases; however, confirmation through parental segregation analysis remains pending. Specifically, OGM identified an intronic insertion in the TTLL5 gene and a deletion in a putative regulatory region approximately 400 kb upstream of the NMNAT1 gene, both of which were missed by prior diagnostic testing. CONCLUSION: Our findings suggest that OGM has potential value in investigating the missing heritability of autosomal recessive disorders. By detecting candidate SVs invisible to conventional methods, OGM may warrant consideration as a complementary diagnostic approach following inconclusive ES; however, larger cohorts and confirmatory functional studies are needed to establish its clinical utility.

Autosomal recessive disorders

Elective genomic sequencing for adults in research, clinical and commercial contexts.

PURPOSE: Elective genomic sequencing (EGS) returns monogenic disease findings in multiple genes, including potentially novel variants, and may also provide participants with carrier status, pharmacogenomic and other health-related information. The PeopleSeq Study assessed participants' motivations for and concerns about EGS and the associated clinical and psychosocial outcomes across diverse EGS providers. METHODS: We administered a shared questionnaire to participants who chose to undergo EGS via 18 academic, clinical, or commercial EGS platforms. RESULTS: We enrolled 1575 participants, of whom 1147 (72.8%) completed a questionnaire after receiving their EGS results. A majority (60.3%) of the participants who completed a post-result questionnaire self-reported receiving results they assessed as important, including negative findings, and 75.9% reported a form of health-related utility. Among a subset (19.4%) who shared their EGS reports, 16.6% (37 of n = 223) received a monogenic finding and self-reported results deemed "important" were consistent with EGS reports. Most participants (74.1%) discussed their results with their family, but fewer discussed their results with a healthcare provider other than the site team (41.7%) or had one or more medical visits as a direct result of their EGS testing (23.1%). Participants expressed diverse motivations for EGS, with 91.4% expressing interest in their personal disease risk and 54% who expressed quasi-indication-based motivations related to family medical history. Individuals motivated by family history reported important results at a significantly higher rate. CONCLUSIONS: Early adopters of EGS are motivated by general interest in their health as well as quasi-indication-based considerations such as family history. A majority of participants learned results they considered medically important, but a much smaller segment engaged healthcare providers with their results.

Genomic testing