Janin Alexandre, Gaudreault Nathalie, Saavedra Armero Victoria, Li Zhonglin, Xu Ran, Boudreau Dominique K, Frenette Lily, Ternacle Julien, Tardif Danielle, Thériault Sébastien, Pibarot Philippe, Mathieu Patrick, Steinberg Christian, Bossé Yohan
Institut universitaire de cardiologie et de pneumologie de Québec - Université Laval, Quebec City, QC G1V 4G5, Canada; Université Claude Bernard Lyon 1, Université de Lyon, Lyon 69008, France.
Institut universitaire de cardiologie et de pneumologie de Québec - Université Laval, Quebec City, QC G1V 4G5, Canada.
HGG Adv. 2025 Aug 8;6(4):100491. doi: 10.1016/j.xhgg.2025.100491.
Lamins A/C, coded by LMNA gene, are crucial for nuclear architecture preservation. Pathogenic LMNA variants cause a wide range of inherited diseases called "laminopathies". A subgroup is referred to "progeroid syndromes" characterized by premature aging and other manifestations including cardiac valve abnormalities. Atypical phenotypes, generally less severe, have also been reported. We report the case of a 26-year-old male with calcific tricuspid aortic and mitral valve diseases. His father was diagnosed with severe aortic valve stenosis and mitral annulus calcification at the age of 38. The goal of this study was to identify the putative variant causing this non-syndromic multivalvular disease. Known disease-causing variants in NOTCH1, FLNA, and DCHS1 were first excluded by Sanger sequencing. Whole-exome sequencing was then performed in five family members. A LMNA variant (p.Glu262Val) was identified with in silico evidences of pathogenicity (CADD [combined annotation dependent depletion] = 33). Cells transfected with the cDNA construct harboring p.Glu262Val were characterized by abnormal nuclear morphology. Along with a literature review, the variant was classified as likely pathogenic. Elucidating the mechanism by which LMNA p.Glu262Val specifically affects cardiac heart valves is likely to provide insight about the pathogenesis of Mendelian forms of valvular heart diseases and may help guide the development of therapies.
由LMNA基因编码的核纤层蛋白A/C对于维持核结构至关重要。致病性LMNA变异会导致多种被称为“核纤层蛋白病”的遗传性疾病。其中一个亚组被称为“早老症综合征”,其特征为早衰以及包括心脏瓣膜异常在内的其他表现。也有非典型表型的报道,通常症状较轻。我们报告了一例患有钙化性三尖瓣和二尖瓣疾病的26岁男性病例。他的父亲在38岁时被诊断出患有严重的主动脉瓣狭窄和二尖瓣环钙化。本研究的目的是确定导致这种非综合征性多瓣膜疾病的潜在变异。首先通过桑格测序排除了NOTCH1、FLNA和DCHS1中已知的致病变异。然后对五名家庭成员进行了全外显子组测序。鉴定出一个LMNA变异(p.Glu262Val),其具有致病性的计算机模拟证据(CADD[综合注释依赖损耗]=33)。用携带p.Glu262Val的cDNA构建体转染的细胞表现出异常的核形态。结合文献综述,该变异被分类为可能致病。阐明LMNA p.Glu262Val特异性影响心脏瓣膜的机制可能会为孟德尔型瓣膜性心脏病的发病机制提供见解,并可能有助于指导治疗方法的开发。