摘要
目的 检测正常人DMPK基因 3′非编码区CTG三核苷酸CTG的分布。方法 采用3 2 P标记的PCR和聚丙烯酰胺凝胶电泳技术 ,对上海地区 5 8例正常人该重复序列进行了分析。结果 在分析的 5 8例正常人 116条染色体中 ,共发现 16种等位基因 ,其中CTG拷贝数以 12拷贝的频率最高 (32 .8% ) ,其余依次为 11拷贝 (2 1.6 % ) ,5拷贝 (2 0 .7% ) ,13拷贝 (16 .4% ) ,14拷贝 (3.4% ) ,15拷贝 (3.4% )和 16拷贝 (1.7% )。纯合子 14例 ,其中 5例 12 /12 ,5例 5 /5 ,3例 11/11,1例 13/13。杂合率为 75 .8%。结论 强直性肌营养不良是DMPK基因 3′非编码区CTG三核苷酸的重复扩增所致。正常人CTG的拷贝数为 5 - 40不等 ,有种族特殊性和高度多态性。
Objective To determine the distribution of CTG trinucleotide repetition in normal subjects. Method Using polymerase chain reaction, the triplet repetition region of the gene of 58 normal subjects from Shanghai was analyzed. Results A total of 16 alleles were found ranging in size from 5 to 16 copies with allele of 12 repetition (32.8%) the most common. The other major alleles were in the range of 5 to 16 repetition (including 21.6% of 11, 20.7% of 5, 16.4% of 13, 3.4% of 14, 3.4% of 15 and 1.7% of 16 repetition, respectively). Heterozygote frenquency in this group was 75.8%. Conclusion Myotonic dystrophy is associated with increasing CTG repetition in the 3′ untranslated region of the myotonin proteinkinase gene (DMPK) located on chromosome 19q133. The CTG repetition in normal subjects vary from 5 to 40 and have racial specificity and high polymorphism. (Shanghai Med J, 2000,23∶656 658.)
出处
《上海医学》
CAS
CSCD
北大核心
2000年第11期656-658,共3页
Shanghai Medical Journal
