AB090. Molecular diagnosis outcome of Duchenne muscular dystrophy gene after 10 years in Vietnam

Background: Duchenne muscular dystrophy (DMD) is the most common allelic X-linked muscular disorder caused by mutation in the dystrophin gene.

Objective: The aims of this study are to investigate mutation rate and characteristic spectrum mutation in dystrophin gene of 564 patients, from January 2005 to December 2015.

Methods: Deletion mutations in the hotspot gene were detected by Multiplex Polymerase Chain Reaction (MPCR). The negative patients with 25 hotspot-exon deletion would be identified mutation using Multiplex Ligation dependent Probe Amplification (MLPA).

Results and conclusions: The rate of mutation is 28.7%. Among 162 mutation patients, 156 patients showed deletions in 25 hotspot regions, accounting for 27.7% of overall mutation ratio. The negative remaining had 6-patient deletion and 10-duplication mutation in the gene fragment analysed. Most of mutation located on the hotspot of the dystrophin gene, including mutations in exon 45-60 (54.4%) and exon 1-19 (28.4%), following is the remaining of the gene (14.3% respectively). All of deletion mutation in hotspot region in Vietnamese DMD patients were accordance with investigated other publications in the word. Distribution and frequency of the most common deletion in Vietnamese DMD patients using MPCR method is demonstrated. MLPA can detect some additional mutations that had been missed by MPCR were detected. But, it is necessary for further analysis for the samples which did not detect any mutation caused of their clinically positive.

Keywords: Duchenne muscular dystrophy (DMD) gene; Multiplex Polymerase Chain Reaction (MPCR); deletion; duplication; Vietnamese Duchenne muscular dystrophy