CTG重复数与强直性肌营养不良的遗传早现现象

CTG repeat numbers and anticipation in Myotonic Dystrophy

目的 研究强直性肌营养不良 (DM)遗传学早现现象与 CTG重复数的关系 ,为 DM遗传早现现象寻找临床及分子理论依据。方法 用长模板扩增 TMPCR法及 DNA杂交法 ,于 8个家系 19个亲代 -子代对成员行强直性肌营养不良蛋白激酶基因 (MTPK)的 CTG重复检测。结果 子代发病年龄较亲代均有提前 ,代间 CTG重复数平均扩增 10 31次 ,CTG重复数与发病年龄间呈负相关 (r值 =- 0 .34,P<0 .0 5 )。结论 DM存在明显的临床早现现象 ,DM遗传学早现现象的分子理论基础为代间的

Objective Through studying the relationship between anticipation in Myotonic Dystrophy(DM) and CTG repeat numbers,biologic and clinical basis for anticipation in DM will be found.Methods CTG repeat numbers of MTPK in 19 parent child pairs of eight pedigree with DM were analyzed by using long expand TM template PCR system.Results All the children had an early age of onset in contrast to that of parents.Expansion of CTG repeat numbers between generations on average was 1031. CTG repeat numbers had a reversal correlation with age of onset in DM(r= 0.34, P <0.05).Conclusion DM has obvious clinical anticipation.The biologic basis of anticipation in DM is expansion of CTG repeat between generations.