Bethlem肌病一家系临床表型及基因突变分析

Analysis of clinical phenotype and gene mutation in a family of Bethlem myopathy

目的分析Bethlem肌病临床表型和基因突变特点。方法报道一家系3例女性患者临床表型、肌电图、肌肉活检、肌肉病理学和基因检测结果,并结合相关文献进行分析。结果先证者于13岁发病,以进行性四肢近端无力为主要临床表现。血清学肌酸激酶水平显著升高,肌电图呈肌源性损害,肌肉病理学显示骨骼肌局灶坏死等非特异性肌源性损害。基因检测显示,先证者及其母、其妹存在相同基因突变,即COL6A3基因错义突变c.4270C>T。结论该家系Bethlem肌病患者为COL6A3基因突变致病,临床通过基因测序手段可提高诊断率,有助于产前诊断,减少遗传病发生率。

Objective To analyze the clinical phenotype and gene mutation characteristics of Bethlem myopathy.Methods The clinical phenotype,electromyography,muscle biopsy,muscle pathology,and gene test results of 3 female patients from a family were reported.Results The protester developed at 13 years old,and the main clinical manifestation was progressive proximal extrem⁃ities weakness.Serological creatine kinase level was significantly increased.EMG showed myogenic damage.Muscle pathology re⁃vealed focal necrosis and regeneration of skeletal muscles,partial loss of striated muscles and varying muscle fiber sizes.Genetic test⁃ing showed that the proband,his mother and his sister had the same gene mutation,namely COL6A3 missense mutation C.4270C>T.Conclusion The disease of Bethlem myopathy is mostly caused by mutations in the COL6A3 gene.In clinical work,gene sequenc⁃ing can increase The diagnosis rate,help prenatal diagnosis,and reduce the incidence of genetic diseases.