Journal of Medical Genetics最新文献

{"title":"Whole-exome sequencing reveals sex difference in the genetic architecture of high myopia.","authors":"Xingchen Liu, Jiacheng Liang, Shasha Li, Yuhe Yang, Qinghao Zhu, Ruowen Qiu, Zheng Ji Chen, Yinghao Yao, Qing Ren, Xiaoguang Yu, Jia Qu, Jianzhong Su, Jian Yuan","doi":"10.1136/jmg-2024-110467","DOIUrl":"10.1136/jmg-2024-110467","url":null,"abstract":"<p><strong>Background: </strong>High myopia (HM) is one of the leading causes of visual impairment and blindness worldwide. To understand the sex difference in the genetic architecture of HM, which may contribute to understanding HM aetiology and help further the realisation of precision medicine for HM.</p><p><strong>Methods: </strong>We performed sex-stratified exome-wide association studies (ExWAS) with n (males)=7492 and n (females)=8090, along with gene- and pathway-based tests and genetic correlation analyses to clarify the variants, genes and molecular pathways that relate to HM in a sex-specific manner.</p><p><strong>Results: </strong>In our ExWAS, we identified that a male-specific gene, <i>CHRNB1</i> (Z_females=1.382, P_females=0.083; Z_males=4.029, P_males=2.80×10^-05; P_difference=0.003), was associated with higher risk scores of HM in males than in females. Rare variant burden tests showed a significant excess of rare protein-truncating variants among HM males in <i>CHRNB1</i>-related pathways, including cell-cell signalling and muscle structure development. Sex-based differences in gene expression within <i>CHRNB1</i>-enriched ciliary body cells were observed; specifically, increased expression of mitochondrial metabolism-related genes in males and antioxidant genes in females. Functional differences in mitochondrial metabolism were confirmed in male-derived H1 and female-derived H9 human embryonic stem cell lines, with H1 cells specifically exhibiting significant dysregulation of mitochondrial organisation and mitochondrial respiratory chain complex assembly after <i>CHRNB1</i> knockdown.</p><p><strong>Conclusion: </strong>Together, our study provides insight into the sex differences in the genetic architecture of HM and highlights <i>CHRNB1</i>'s role in HM pathogenesis in males.</p>","PeriodicalId":16237,"journal":{"name":"Journal of Medical Genetics","volume":" ","pages":"358-368"},"PeriodicalIF":3.5,"publicationDate":"2025-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143624999","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of NICE Guideline NG241 'Ovarian Cancer: identifying and managing familial and genetic risk' on a regional NHS family history and clinical genetics service.","authors":"Alexander Roe, Andrea Forman, Fiona Lalloo, Terri P McVeigh, Helen Hanson, Katie Snape","doi":"10.1136/jmg-2024-110481","DOIUrl":"10.1136/jmg-2024-110481","url":null,"abstract":"<p><strong>Background: </strong>NICE Guideline NG241: identifying and managing familial and genetic risk of ovarian cancer (OC) was published by the National Institute for Health and Care Excellence (NICE) in March 2024. NG241 advises germline genetic testing of genes predisposing to OC in unaffected individuals with an OC family history at different mutation likelihood thresholds depending on age and sex, ranging from 2% to 10% likelihood of finding a germline pathogenic variant (GPV). Prior to implementation of NG241, updates to the NHS England National Genomic Test Directory would be required. Clinical genetics services have to consider equity of access to assessment and testing across all familial cancer types, best use of their limited resources and other factors such as complexity of delivery of clinical pathways.</p><p><strong>Methods: </strong>We analysed data from 8011 patients who provided digital family histories to the South West Thames Centre for Genomics between October 2019 and June 2024.</p><p><strong>Results: </strong>We estimate 527/782 (68%) females and 28/77 (36%) males would meet test criteria for NICE NG241. We estimate we would reject 2919/5485 (53%) females and 135/1208 (11%) males with the same likelihood of carrying a GPV, but with a breast cancer rather than OC family history. Testing the familial OC cohort at a universal 5% threshold in OC families would detect ~11 carriers for 229 tests compared with ~8 carriers for 278 tests following NG241 criteria.</p><p><strong>Conclusion: </strong>Our data highlight additional factors needing to be considered before the NICE Guideline NG241 can be implemented by regional genetics services.</p>","PeriodicalId":16237,"journal":{"name":"Journal of Medical Genetics","volume":" ","pages":"311-316"},"PeriodicalIF":3.5,"publicationDate":"2025-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12015086/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143458222","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gene prioritisation for enhancing molecular diagnosis in rare skeletal muscle disease cohort.","authors":"Victoria Lillback, Gaber Bergant, Maria Francesca Di Feo, Ivana Babić Bozović, Annalaura Torella, Mridul Johari, Aleš Maver, Katarina Pelin, Filippo M M Santorelli, Vincenzo Nigro, Peter Hackman, Borut Peterlin, Bjarne Udd, Marco Savarese","doi":"10.1136/jmg-2024-110212","DOIUrl":"10.1136/jmg-2024-110212","url":null,"abstract":"<p><strong>Background: </strong>Inherited rare skeletal muscle diseases cause muscle weakness and wasting of variable severity. Without a molecular diagnosis, patients often endure prolonged diagnostic journeys, leading to delays in appropriate management of the disease. This occurs in approximately 60% of patients with rare diseases.</p><p><strong>Methods: </strong>To facilitate reanalysis of 278 unsolved patients, we used a gene prioritisation tool Exomiser, which standardises analysis by ranking causative variants based on phenotype relevance and variant pathogenicity. Before analysis, we benchmarked Exomiser for variant prioritisation with solved cases and for novel disease gene discovery with mock cases with variants in candidate disease genes. Additionally, we studied the significance of the specificity of the phenotype descriptions.</p><p><strong>Results: </strong>In our study, Exomiser ranked genes in the top 10 correctly in 97.4% of controls with previously detected causative variants. Moreover, 57.1% of candidate genes in mock cases were similarly prioritised in the top 10. We also showed that three parental muscle disease human phenotype ontologies describing the patient phenotype performed as well as patient-specific ones, with a p value of 0.68 for difference in performance. The provided automation and standardisation of variant interpretation resulted in two novel diagnoses and in findings, either in known muscle disease genes or in novel candidate genes, which need further investigation.</p><p><strong>Conclusions: </strong>Exomiser is recommended for initial and periodic reanalyses of exomes in unsolved patients with myopathy, as it benefits from literature updates and minimises effort. This approach could also extend to whole genome sequencing data, aiding the interpretation of variants beyond coding regions.</p>","PeriodicalId":16237,"journal":{"name":"Journal of Medical Genetics","volume":" ","pages":"350-357"},"PeriodicalIF":3.5,"publicationDate":"2025-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143566586","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Homozygous loss of function variant in <i>LMNB2</i> gene causes major brain malformation and perinatal death.","authors":"Camille Desgrouas, Igor Deryabin, Clémence Duvillier, Diane Frankel, Elise Kaspi, Thibaud Quibel, Gabriel Le Goff, Mathieu Cerino, Jérémie Mortreux, Bénédicte Gérard, Rodolphe Dard, Catherine Badens","doi":"10.1136/jmg-2024-110549","DOIUrl":"10.1136/jmg-2024-110549","url":null,"abstract":"<p><p>Lamins play a major role in the mechanical stability of cell nuclei, the organisation of chromatin and the DNA replication, transcription and repair. The expression profiles of A-type and B-type lamins vary depending on developmental stages, cell types and tissues. Lamin B2 is expressed very early in embryogenesis, especially in the central nervous system, where it is essential for neuronal migration and brain development. Pathogenic missense variants in lamin B2 have been linked to conditions such as lipodystrophy, progressive myoclonic epilepsy and primary microcephaly. Here, we report clinical data and molecular findings for two related newborns carrying a homozygous loss-of-function variant in the <i>LMNB2</i> gene. Both newborns died in the perinatal period and exhibited a similar phenotype at birth, including severe brain development abnormalities, which closely mirror findings observed in several <i>Lmnb2</i>-deficient mouse models. Western blot and immunofluorescence cell labelling performed on the patient's fibroblasts obtained at birth confirmed the complete absence of lamin B2 and revealed an increase in lamin B1, together with alterations in alpha-tubulin and vimentin organisation. This novel clinical form of laminopathy associated with lamin B2 deficiency expands the molecular causes of brain development abnormalities to <i>LMNB2</i> gene variants.</p>","PeriodicalId":16237,"journal":{"name":"Journal of Medical Genetics","volume":" ","pages":"345-349"},"PeriodicalIF":3.5,"publicationDate":"2025-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143515904","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Uptake, utility and resource requirements of a genetic counselling telephone helpline within the BRCA-DIRECT digital pathway for mainstreamed BRCA testing in patients with breast cancer.","authors":"Bethany Torr, Grace Kavanaugh, Monica Hamill, Christopher Jones, Helena Harder, Sophie Allen, Alice Garrett, Subin Choi, Rosalind Way, Rochelle Gold, Amy Taylor, Rhian Gabe, Anneke Lucassen, Ranjit Manchanda, Angela George, Michael Hubank, Stephen Bremner, Ashu Gandhi, Zoe Kemp, D Gareth Evans, Lesley Fallowfield, Valerie Jenkins, Clare Turnbull","doi":"10.1136/jmg-2024-110428","DOIUrl":"10.1136/jmg-2024-110428","url":null,"abstract":"<p><strong>Background: </strong>We trialled the first digital pathway (BRCA-DIRECT) aiming to improve capacity for mainstreamed BRCA testing within UK breast oncology services. Patients received standardised digital pretest information, with saliva sampling and consent to testing completed at home. For individualised support, we offered access to a clinical genetics professional via a telephone helpline (TH).</p><p><strong>Methods: </strong>To evaluate the utilisation, uptake and resource requirements for provision of the TH, we analysed data from structured call logs recorded in the BRCA-DIRECT Study. Mixed-methods analysis included combining quantitative data from call logs and patient demographics with thematic analysis of free-text notes establishing reasons for calls. Additional data were analysed from structured telephone interviews.</p><p><strong>Results: </strong>Calls were received from 201/1140 (17.6%) patients. We identified that 84.6% of calls (274 calls, 1097 min) pertained to 'administrative' support needs only. The remaining 15.4% required a clinical genetics professional (50 calls, 344 min). Of the clinical calls received: 26.0% were placed prior to test consent, 36.0% while awaiting results and 38.0% post results, with median (interquartile) call lengths of 8 (4-10) min; 5.5 (4-10) min; and 5 (3-7) min, respectively. Across all 1140 patients, a mean of 0.3 min of clinical time was required per patient.</p><p><strong>Conclusions: </strong>Our findings demonstrate that the 'BRCA-DIRECT' model of standardised information provision served most patients, with a minority using the helpline for supplementary clinical information or support. The modest per-patient requirement for clinical time supports the scalability of this model for expanding mainstream genetic testing within UK oncology services.</p>","PeriodicalId":16237,"journal":{"name":"Journal of Medical Genetics","volume":" ","pages":"317-325"},"PeriodicalIF":3.5,"publicationDate":"2025-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12015060/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143624998","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimising the molecular investigation of the FSHD locus: an integrated workflow using single molecule optical mapping and Southern blot analysis.","authors":"Joowon Jang, Hobin Sung, Jung-Ae Lee, Sung Im Cho, Jee-Soo Lee, Moon-Woo Seong","doi":"10.1136/jmg-2024-110382","DOIUrl":"https://doi.org/10.1136/jmg-2024-110382","url":null,"abstract":"<p><strong>Purpose: </strong>Facioscapulohumeral muscular dystrophy (FSHD) is a genetic disorder caused by contraction or hypomethylation of the D4Z4 repeat array located at chromosome 4q35. For the disease to manifest, a permissive haplotype is required, as it enables the pathogenic expression of the <i>DUX4</i> gene. FSHD cases often involve complex rearrangements, such as intrachromosomal rearrangements and translocations, which complicate diagnosis using conventional methods. This study focuses on evaluating the diagnostic potential of single molecule optical mapping (SMOM) for FSHD with complex rearrangements, particularly in cases involving 4q-10q translocations, which present challenges for detection by SMOM alone. Furthermore, we propose an integrated diagnostic strategy, combining SMOM with complementary methods, to improve accuracy in these challenging cases.</p><p><strong>Methods: </strong>We reviewed the test results of 238 patients with suspected FSHD, and 25 participants with presumed complex rearrangements were included in this study. SMOM was performed on these participants, and the results were manually reviewed and compared with those obtained from Southern blot (SB) analysis.</p><p><strong>Results: </strong>Nine patients carrying 4q-10q translocation exhibited discrepancies between the two methods. Linear regression analysis revealed a significant discrepancy in chromosomal assignment between SB and SMOM in cases suspected of translocation.</p><p><strong>Conclusions: </strong>Given the complex nature of FSHD, none of the current methods can independently provide a definitive diagnosis. As misdiagnosis may occur when relying on a single technique, we propose an integrated diagnostic approach, with SMOM as the first-line test.</p>","PeriodicalId":16237,"journal":{"name":"Journal of Medical Genetics","volume":" ","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144024661","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of higher-than-expected control population allele frequency on classification of loss-of-function variants in cancer susceptibility genes.","authors":"Miriam J Smith, George J Burghel, D Gareth Evans","doi":"10.1136/jmg-2025-110703","DOIUrl":"https://doi.org/10.1136/jmg-2025-110703","url":null,"abstract":"<p><p>A query was sent to the cancer predisposition gene variant database Cancer Variant Interpretation Group UK, on the nonsense variant in NM_032043.3(<i>BRIP1</i>):c.2392C>T,p.(Arg798Ter). The submitter classified this as a variant of uncertain significance, providing very strong variant effect evidence with the intention of adding supporting pedigree information, according to the guidelines used for classification. However, the relatively high population frequency in the UKB cohort of 367/439 920 (0.083%) was a concern as it is higher than expected for the disease frequency, which would reduce the predicted pathogenicity score. This situation highlights the increasing concerns over the use of population data in pathogenicity classification of truncating/loss-of-function (LoF) variants in known cancer predisposition genes, particularly since the addition of UKB control data. Here, we have conducted a series of case-control comparisons for common truncating variants in known breast/ovarian cancer-associated genes, as well as <i>LZTR1</i>-related schwannomatosis, to address this issue using our Manchester cancer screening population compared with controls in UKB data.Our data show strong ORs for these common truncating variants. We propose that for truncating variants in cancer susceptibility genes with a significant case-control OR, apparently conflicting population frequency evidence criteria should be avoided.</p>","PeriodicalId":16237,"journal":{"name":"Journal of Medical Genetics","volume":" ","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144029917","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Economic evaluation of personalised versus conventional risk assessment for women who have undergone testing for hereditary breast and ovarian cancer genes: a modelling study.","authors":"Qin Xi, Nichola Fennell, Stephanie Archer, Marc Tischkowitz, Antonis C Antoniou, Stephen Morris","doi":"10.1136/jmg-2024-109948","DOIUrl":"https://doi.org/10.1136/jmg-2024-109948","url":null,"abstract":"<p><strong>Background: </strong>The management of women with germline pathogenic variants (GPVs) in breast (BC) and ovarian cancer (OC) susceptibility genes is focused on surveillance and risk-reducing surgery/medication. Most women are assigned an average range of risk and treated accordingly, but it is possible to personalise this. Here, we explore the economic impact of risk personalisation.</p><p><strong>Method: </strong>We compared two strategies for risk stratification for female participants: conventional risk assessment (CRA), which only involves information from genetic testing and personalised risk assessment (PRA), using genetic and non-genetic risk modifiers. Three different versions of PRA were compared, which were combinations of polygenic risk score and questionnaire-based factors. A patient-level Markov model was designed to estimate the overall National Health Service cost and quality-adjusted life years (QALYs) after risk assessment. Results were given for 20 different groups of women based on their GPV status and family history.</p><p><strong>Results: </strong>Across the 20 scenarios, the results showed that PRA was cost-effective compared with CRA using a £20 000 per QALY threshold in women with a GPV in <i>PALB2</i> who have OC or BC+OC family history, and women with a GPV in <i>ATM</i>, <i>CHEK2</i>, <i>RAD51C</i> or <i>RAD51D</i>. For women with a GPV in <i>BRCA1</i> or <i>BRCA2</i>, women with no pathogenic variant and women with a GPV in <i>PALB2</i> who have unknown family history or BC family history, CRA was more cost-effective. PRA was cost-effective compared with CRA in specific situations predominantly associated with moderate-risk BC GPVs (<i>RAD51C</i>/<i>RAD51D</i>/<i>CHEK2</i>/<i>ATM</i>), while CRA was cost-effective compared with PRA predominantly with high-risk BC GPVs (<i>BRCA1</i>/<i>BRCA2</i>/<i>PALB2</i>).</p><p><strong>Conclusion: </strong>PRA was cost-effective in specific situations compared with CRA in the UK for assessment of women with or without GPVs in BC and OC susceptibility genes.</p>","PeriodicalId":16237,"journal":{"name":"Journal of Medical Genetics","volume":" ","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144006961","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"<i>LSM1</i> c.231+4A>C hotspot variant is associated with a novel neurodevelopmental syndrome: first patient cohort.","authors":"Sivan Reytan Miron, Alina Kurolap, Bassam Abu-Libdeh, Abdel Salam Abu-Libdeh, Clara Velmans, Florian Erger, Vera Riehmer, Tzung-Chien Hsieh, Hellen Lesmann, Adi Reches, Chofit Chai Gadot, Adi Mory, Motee Al-Ashhab, Christian Netzer, Nadirah Damseh, Hagit Baris Feldman","doi":"10.1136/jmg-2024-110574","DOIUrl":"https://doi.org/10.1136/jmg-2024-110574","url":null,"abstract":"<p><strong>Background: </strong>The <i>LSM1</i> gene encodes a subunit of the conserved LSM1-7 protein complex involved in messenger RNA (mRNA) metabolism. Variants in the <i>LSM1</i> gene have been described in two separate case reports. The first published report identified the homozygous splice-site variant c.231+4A>C, while the second reported a homozygous missense variant. Nevertheless, variation in <i>LSM1</i> has yet to be established as disease-causing in humans.</p><p><strong>Methods: </strong>Through exome sequencing and detailed phenotyping, we report six syndromic paediatric patients with the homozygous c.231+4A>C variant in the <i>LSM1</i> gene, collected via GeneMatcher. GestaltMatcher was used to analyse facial feature similarity, and real-time quantitative PCR (RT-qPCR) confirmed the splice defect caused by the variant. Haplotype analysis assessed whether this variant resulted from independent occurrences or a common ancestral haplotype.</p><p><strong>Results: </strong>Patients presented with dysmorphic facial features, developmental delay and multisystemic involvement, including urological, cardiac and skeletal manifestations, showcasing the phenotypic spectrum of this syndrome. RT-qPCR confirmed that the c.231+4A>C variant causes exon 3 skipping, producing negligible <i>wild-type LSM1</i> mRNA expression. Elevated mutant isoform expression confirmed pathogenicity according to the American College of Medical Genetics and Genomics (ACMG) guidelines. We identified this variant in the Muslim Arab and Ashkenazi Jewish populations and determined that it represents a hotspot variant through haplotype analysis.</p><p><strong>Conclusion: </strong>Our findings establish <i>LSM1</i>, and specifically the c.231+4A>C homozygous variant, as causative for a novel autosomal recessive syndromic neurodevelopmental disorder. These results expand the understanding of <i>LSM1</i>-related diseases and provide a foundation for further investigation of its molecular mechanisms.</p>","PeriodicalId":16237,"journal":{"name":"Journal of Medical Genetics","volume":" ","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144015469","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Short stature, brachydactyly and joint contractures associated with novel <i>FBN2</i> variants in two families.","authors":"Petra Loid, Fan Wang, Otto Lennartsson, Mari Muurinen, Alice Costantini, Sakshi Vats, Maria Lodefalk, Ola Nilsson, Outi Mäkitie","doi":"10.1136/jmg-2024-110533","DOIUrl":"https://doi.org/10.1136/jmg-2024-110533","url":null,"abstract":"<p><strong>Background: </strong>Fibrillinopathies comprise allelic disorders with opposing phenotypes. Pathogenic variants in fibrillin-2, encoded by <i>FBN2</i>, have mainly been associated with congenital contractural arachnodactyly but in a few cases also with brachydactyly.</p><p><strong>Methods and results: </strong>We recruited two families with index patients presenting with short stature (heights ≤3 SD scores), brachydactyly, joint contractures and facial dysmorphism as major features. In Family 2, the proband and father also had carpal tunnel syndrome. Radiographs showed signs of mild skeletal dysplasia with short long bones, brachydactyly and mild metaphyseal and vertebral irregularity. Whole genome sequencing revealed novel variants in the <i>FBN2</i> gene that segregated with the phenotype: in Family 1, a novel heterozygous missense variant c.4862G>A, p.(Cys1621Tyr) and in Family 2, a novel heterozygous deletion of exons 9-11. The missense variant affects a highly conserved residue and is predicted to be deleterious by most in silico tools. The <i>FBN2</i> deletion affects a well-conserved region and leads to loss of the transforming growth factor β binding-like 2 domain and part of the calcium-binding epidermal growth factor-like domain.</p><p><strong>Conclusion: </strong>Our findings suggest that short stature and mild skeletal dysplasia might be part of the spectrum of <i>FBN2-</i>related phenotypes. The study supports the role of <i>FBN2</i> variants in growth failure and expands the molecular spectrum of <i>FBN2</i> variants.</p>","PeriodicalId":16237,"journal":{"name":"Journal of Medical Genetics","volume":" ","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143811499","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}