目的了解中国汉族假性肥大性肌营养不良症(DMD/BMD)患儿基因缺失突变的特点。方法经PCR和20对引物，对964例疑似DMD/BMD患儿Dystophin基因外显子缺失突变类型及断裂点进行检测分析。结果有491例患儿(491/964，51.0％)存在基因缺失突变:其中75例基因缺失突变位于基因5’端区域(15.2%)，402例基因缺失突变位于基因中央区域(81.7%)，13例基因缺失突变范围跨越了以上两个区域(2.6％)。检测到以50、49、48号外显子缺失突变最为常见。74％患儿的Dystophin基因断裂点位于44~50号内含子，以44号内含子最多(21％)。结论20对引物的PCR法能够检测超过半数的Dystrophin基因缺失突变，基因中央区缺失是中国汉族DMD/BMD患儿病例的主要基因缺失突变类型。
Objective To investigate the distribution feature of dystrophin gene deletion mutations in Chinese Han Duchenne/Becker muscular dystrophy (DMD/BMD)pediatric patients. Methods Determination of deletion mutation in dystophin gene of 964 DMD/BMD suspected pediatric patients was performed by amplifying 20 segments of major deletion “hot spot” region with polymerase chain reaction (PCR).The deletion pattern of dystophin gene was consequently summarized and the distribution of breakpoints of dystophin gene deletion mutation was also analyzed.Results The total 491cases (51.0%) had confirmed deletion mutations. Mutations in 75 cases (15.2%) located in the region of 5’-flanking region, 402 cases (81.7%) in the region of central region,and 13 cases (2.6%) deletions span in both 5’-flanking and central regions.The most common deletions including exon 50, 49 and 48 deletions ranked the top. 74％of deletion breakpoints fell in introns 44~50 in dystophin gene, in which about 21% of deletion breakpoints fell in intron 44. Conclusion The study indicates that more than half of suspected DMD/BMD cases are confirmed deletion mutation in dystophin gene. Deletion mutations are mostly distributed in the central region of DMD gene in Chinese Han pediatric population.
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