Application of next-generation sequencing in the molecular diagnosis of Duchenne muscular dystrophy

Abstract:

The purpose of this study is to analyze the family's clinical data of 22 children who were given an intended clinical diagnosis of Duchenne muscular dystrophy (DMD), and to explore the clinical value of next-generation sequencing (NGS) in the molecular diagnosis of DMD. The probands were simultaneously tested by NGS for a gene panel associated with hereditary neuromuscular disease and multiplex ligation-dependent probe amplifcation (MLPA) for the Dystrophin gene. The exon deletion/repetition mutations of the Dystrophin gene determined by both methods were compared and the point mutations of the Dystrophin gene were verifed by Sanger sequencing. Dystrophin gene mutations were found in all the 22 probands, including 14 exon deletion/repetition mutations and 8 point mutations/minor variations. The results of MLPA detection were consistent with those of NGS. The results of Sanger sequencing showed that the point mutations and minor variations determined by NGS were correct. One missense mutation (c.6290G>T), 1 nonsense mutation (c.3487C>T) and 4 minor deletion-induced frameshift mutations (c.1208delG, c.7497_7506delGGTGGGTGAC, c.9421_9422delAA and c.8910_8913delTCTC) had not been reported in the Human Gene Mutation Database, and thus were considered as novel mutations of the Dystrophin gene. The results of this study showed that NGS can detect variations in the Dystrophin gene, including exon deletion/repetition, point mutation, minor deletion and intron mutation. Therefore, NGS is of certain clinical value in the molecular diagnosis of DMD and is worthy of recommendation.