SCA7基因的克隆揭示了一个高度不稳定的CAG重复序列扩增。

Cloning of the SCA7 gene reveals a highly unstable CAG repeat expansion.

作者信息

David G, Abbas N, Stevanin G, Dürr A, Yvert G, Cancel G, Weber C, Imbert G, Saudou F, Antoniou E, Drabkin H, Gemmill R, Giunti P, Benomar A, Wood N, Ruberg M, Agid Y, Mandel J L, Brice A

机构信息

INSERM U289, Hôpital de la Salpêtrière, Paris, France.

出版信息

Nat Genet. 1997 Sep;17(1):65-70. doi: 10.1038/ng0997-65.

DOI:10.1038/ng0997-65

PMID:9288099

Abstract

The gene for spinocerebellar ataxia 7 (SCA7) has been mapped to chromosome 3p12-13. By positional cloning, we have identified a new gene of unknown function containing a CAG repeat that is expanded in SCA7 patients. On mutated alleles, CAG repeat size is highly variable, ranging from 38 to 130 repeats, whereas on normal alleles it ranges from 7 to 17 repeats. Gonadal instability in SCA7 is greater than that observed in any of the seven known neuro-degenerative diseases caused by translated CAG repeat expansions, and is markedly associated with paternal transmissions. SCA7 is the first such disorder in which the degenerative process also affects the retina.

摘要

脊髓小脑共济失调7型（SCA7）基因已被定位到3号染色体的p12 - 13区域。通过定位克隆，我们鉴定出一个功能未知的新基因，该基因包含一个CAG重复序列，在SCA7患者中此重复序列发生了扩增。在突变等位基因上，CAG重复序列的大小高度可变，范围从38到130个重复，而在正常等位基因上，其范围为7到17个重复。SCA7中的性腺不稳定性大于由翻译后的CAG重复序列扩增引起的七种已知神经退行性疾病中的任何一种，并且与父系遗传显著相关。SCA7是第一种其退行性病变过程也累及视网膜的此类疾病。