New multiplex-PCR assay for detection of deletions of DMD gene in Chinese DMD patients

Abstract

Objective To establish a new multiplex-PCR assay to improve the detection rate of mutations in the DMD gene in Chinese patients. Methods A retrospective review of DMD deletion spectrum of 355 DMD patients with deletions all over the gene was performed. All deletions were confirmed by one-step diagnostic procedure and MLPA analysis. The exons with high frequency of mutations were identified to constitute the amplification system and the PCR conditions were optimized. Results Two new multiplex-PCR assays were established. Assay one was used to detect 10 exons including exon 5, 8, 17, 44, 45, 47, 49, 50, 51 and 52 of DMD gene, in two PCR sets. The theoretical detection rate would be 92% (326/355). Assay two was used to detect 5 exons including exon 12, 19, 35, 43 and 54, which could be used to screen additional 5% (17/355) deletion cases. The method was validated in other 22 DMD patients. Multiplex-PCR results were completely identical to the MLPA results in all 22 DMD patients. Conclusions The two multiplex-PCR assays were established based on the analysis of 355 Chinese DMD patients with gene deletions. It is believed that the new approach would be more applicable for deletion detection on the Chinese DMD patients since the DMD cases involved were from the whole country. Key words: Muscular dystrophy, duchenne; Dystrophin; Gene deletion; Polymerase chain