LMNA基因新生突变相关肢带型肌营养不良1B型1例报告并文献复习

LMNA gene de novo mutation related limb-girdle muscular dystrophy 1 B: a case report and literature review

目的了解LMNA基因突变相关的肢带型肌营养不良1B型(LGMD 1B)的临床表型、诊断及遗传学特点。方法回顾分析1例LMNA基因新生突变引起的LGMD 1B患儿的临床及分子遗传学资料,并复习相关文献。结果女性患儿,5岁,主要表现为双下肢明显无力、上肢轻度无力。基因检测显示LMNA基因存在c.1580G>C杂合错义突变,该突变导致第527号氨基酸由Arg变为Pro。患儿父母、2个姐姐及妹妹在该位点均为野生型。患儿确诊为LMNA基因新生突变引起的LGMD 1B型。LMNA基因为LGMD 1B的致病基因。基因突变引起肌细胞功能蛋白异常,累及肌纤维所有结构。结论 LMNA基因检测可早期诊断LGMD 1B型。

Objectives To explore the clinical phenotypes,diagnosis and genetic characteristics of LMNA related limbgirdle muscular dystrophy 1 B(LGMD IB).Methods The clinical data of one case of limb-girdle muscular dystrophy 1 B with LMNA gene mutation were retrospectively analyzed.The related literatures were reviewed.Results The proband,a 5 yearold female,presented with weakness of lower extremities,and mild upper limb weakness.Mutation screening of LMNA gene in the proband and their parents,three sisters identified a de novo heterozygous missense mutation of c.1580 G>C(p.Arg527 Pro)in LMNA.She was confirmed as LMNA gene mutation related limb-girdle muscular dystrophy 1 B.The literature search revealed limb-girdle muscular dystrophy 1 B and LMNA gene-related children is a kind of myopathy in the proximal limb muscles(pelvic and shoulder girdle muscle)muscle weakness as the main manifestation of myopathy,and may accompanied with heart block and dilated cardiomyopathy.The LMNA gene is a causative gene of LGMD IB,and its mutations cause muscle cell dysfunction involving all structures of muscle fibers.Conclusions LMNA gene screening is conducive to early diagnosis of limb-girdle muscular dystrophy 1 B.