Tang Yanping, Wang Ying, Yang Ping, Liu Yuan, Wang Bo, Podolsky Robert, McIndoe Richard, Wang Cong-Yi
Department of Cell Biology and Genetics, Tongji Medical College of Huazhong University of Science and Technology, Wuhan, China.
Am J Med Genet B Neuropsychiatr Genet. 2006 Apr 5;141B(3):242-4. doi: 10.1002/ajmg.b.30261.
The prevalence of juvenile-onset Huntington's disease (HD) is about ten times lower than adult HD. Here we report a Chinese HD family showing both intergeneration CAG expansion and contraction. The expansion resulted from a paternal transmission which leads to juvenile-onset HD for a 17-year-old Chinese boy (III-5). More interestingly, a contraction was noticed in a maternal transmission (III-3), which changed the CAG repeat from an expanded, disease-causing allele (48 repeats) to a normal or intermediate allele (34 repeats). Of note, the contraction resulted in a deletion of 14 CAG repeats, which is much larger than previously reported contractions. Our results are consistent with previous observations in Western Caucasians that juvenile-onset HD is more likely inherited through the male germline.
青少年型亨廷顿舞蹈症（HD）的患病率比成人型HD低约十倍。在此，我们报告一个中国HD家系，该家系呈现出代际间CAG重复序列的扩增和收缩。扩增源于父系遗传，导致一名17岁中国男孩（III-5）患青少年型HD。更有趣的是，在母系遗传（III-3）中发现了收缩现象，这使得CAG重复序列从一个扩增的致病等位基因（48次重复）变为一个正常或中间等位基因（34次重复）。值得注意的是，收缩导致14个CAG重复序列缺失，这比先前报道的收缩要大得多。我们的结果与先前在西方高加索人中的观察结果一致，即青少年型HD更有可能通过雄性生殖系遗传。
