
先天性肌营养不良1C型1例临床特点和FKRP基因突变分析
Clinical features and FKRP mutations of congenital muscular dystrophy 1C
先天性肌营养不良1C型(MDClC)是由FKRP基因纯合或复合杂合突变引起。该文报道1例MDClC患儿的临床和基因突变特点。患儿,男,8月龄,因发育落后就诊。临床表现为翻身不佳、独坐不稳,肌张力低下,膝腱、跟腱反射不能引出,表情刻板,眼内斜视。基因检测证实患儿FKRP基因存在c.350C > G和c.1303C > T复合杂合突变;c.350C > G来自于母亲,为已报道的致病性错义突变;c.1303C > T来自于父亲,是新发错义突变,生物信息学软件分析预测其有致病可能。结合患儿早发肌张力低下、运动发育落后的临床特征和FKRP基因突变测序结果,确诊为MDC1C。
Congenital muscular dystrophy type 1C (MDC1C) is caused by the homozygous or compound heterozygous mutations of the FKRP gene. This article reported the clinical and mutation features of a child with MDC1C. The boy aged 8 months visited the hospital due to delayed development. As for clinical manifestations, the boy could not turn over or sit stably by himself, and there was a significant reduction in muscle tension; biceps reflex in both upper extremities and patellar tendon reflex and Achilles tendon reflex in both lower extremities could not be induced. The boy also had a stereotyped facial expression and strabismus. Gene detection revealed c.350C > G and c.1303C > T compound heterozygous mutations in the FKRP gene. The c.350C > G mutation came from the mother and had been reported as a pathogenic missense mutation. The c.1303C > T mutation came from the father and was a new missense mutation, and a bioinformatics analysis showed that it might be a pathogenic mutation. The boy was diagnosed with MDC1C with reference to the clinical features of hypotonia and motor developmental delay and FKRP gene mutation sequencing.
先天性肌营养不良1C型 / Fukutin相关蛋白 / FKRP基因 / α-抗肌萎缩相关糖蛋白 / 婴儿
Congenital muscular dystrophy 1C / Fukutin-related protein / FKRP gene / α-Dystroglycan / Infant
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