Daniels R J, Campbell L, Rodrigues N R, Francis M J, Morrison K E, McLean M, MacKenzie A, Ignatius J, Dubowitz V, Davies K E
Institute of Molecular Medicine, John Radcliffe Hospital, Headington, Oxford, UK.
J Med Genet. 1995 Feb;32(2):93-6. doi: 10.1136/jmg.32.2.93.
Autosomal recessive childhood onset spinal muscular atrophy has been mapped to chromosome 5q13. We report the analysis of a polymorphic microsatellite which shows linkage disequilibrium with the disease. The linkage disequilibrium is observed with a null allele which is seen as the non-inheritance of alleles from one or both parents. The inheritance of a null allele was observed in 26 out of 36 (72%) informative childhood onset spinal muscular atrophy (SMA) families tested, of all types of severity and from a variety of ethnic backgrounds. In seven families segregating for the severe Werdnig-Hoffmann or SMA type I, no alleles were inherited from either parent using this microsatellite. This null allele may represent a deletion which is either closely associated with, or causes, the disease.
常染色体隐性遗传性儿童期发病的脊髓性肌萎缩症基因已被定位于5号染色体长臂13区。我们报告了一个多态性微卫星的分析结果，该微卫星与该疾病存在连锁不平衡。这种连锁不平衡是通过一个无效等位基因观察到的，该等位基因表现为一个或两个亲本的等位基因未被遗传。在36个进行检测的信息充分的儿童期发病的脊髓性肌萎缩症（SMA）家系中，有26个（72%）观察到无效等位基因的遗传，这些家系涵盖了所有严重程度类型，且来自不同种族背景。在7个分离出严重的韦尔尼克 - 霍夫曼病或I型脊髓性肌萎缩症的家系中，使用该微卫星未发现有任何等位基因从任一亲本遗传而来。这个无效等位基因可能代表一种与疾病紧密相关或导致疾病的缺失。
