LAMA2双等位基因致病性变异导致先天性肌营养不良1A型（CMD1A）。该研究患儿为19月龄男孩，临床表现为运动发育落后，伴血清肌酸激酶、转氨酶及乳酸脱氢酶升高。遗传学分析发现患儿LAMA2基因存在复合杂合变异，其中母源性c.7147C > T （p.Ala2383Ter）为已报道的无义变异，而父源性c.8551_8552insAA （p.Ile2852ArgfsTer2）为未报道的移码变异，且根据ACMG指南确定为致病性变异。该患儿最终确诊为CMD1A。国内外文献复习发现：该病患儿多在生后6个月内起病，以严重的运动发育落后为特点，伴有血清肌酸激酶升高，可有脑白质受累的影像学改变；LAMA2基因变异具有明显的异质性，且绝大部分属于零效变异；目前CMD1A患儿无特异性治疗，远期预后不良。
Abstract：Biallelic pathogenic mutations of the LAMA2 gene result in congenital muscular dystrophy type 1A (CMD1A). The patient in this study was a boy aged 19 months, with the clinical manifestations of motor development delay and increases in the serum levels of creatine kinase, aminotransferases, and lactate dehydrogenase. Genetic analysis showed that the patient had compound heterozygous mutations in the LAMA2 gene, among which c.7147C > T (p.Ala2383Ter) from his mother was a known nonsense mutation, and c.8551_8552insAA (p.Ile2852ArgfsTer2) from his father was a frameshift mutation which had never been reported before and was identified as a pathogenic mutation based on the ACMG guideline. The boy was confirmed with CMD1A. A literature review of related articles in China and overseas revealed that most children with CMD1A have disease onset within 6 months after birth, with the features of motor developmental delay, elevated serum creatine kinase, and white matter impairment on imaging examination. The mutations of the LAMA2 gene have remarkable heterogeneity, the majority of which are null mutations. There are no specific treatment methods for CMD1A currently, and children with CMD1A usually have a poor long-term prognosis.
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