Tiny mutations of Duchenne muscular dystrophy gene in 45 patients with Duchenne muscular dystrophy

Objective To investigate the characteristics of point mutation, deletion or insertion mutations in Duchenne muscular dystrophy (DMD) gene. Methods Clinically confirmed 45 DMD patients without deletion/duplication mutation confirmed by MLPA in our hospital from January 2011 to November 2016 were chosen. Two generation sequencing technology was employed to detect DMD gene sequences. The features of tiny mutations were analyzed and summarized. Results In 45 patients without deletion/repeat mutation DMD, there were 66 mutations, including 24 missense mutations, 20 nonsense mutations, 12 splice site mutations, 9 frameshift mutations and one synonymous mutation. There were 29 patients carrying one mutation, 8 patents carrying 2 mutations, 4 patients carrying 3 mutations, 4 patients carrying 3 mutations, and one patient carrying 5 mutations. The exon 48 missense mutations were the most common, followed by exon 37 and exon 59; nonsense mutations, frameshift mutations, splice site mutations, and synonymous mutations had no obvious concentration distribution trend. Conclusion The exons 48, 37 and 59 should be mainly considered during the drug research and development of tiny mutations, and readingthrough treatment of nonsense mutations is suitable for nonsense mutations. Key words: Duchenne muscular dystrophy; Gene sequencing; Tiny mutation