一个脊髓小脑共济失调1型（SCA1）家系中的基因型/表型相关性：无CAG重复序列扩增的遗传早现现象

Genotype/phenotype correlation in a SCA1 family: anticipation without CAG expansion.

作者信息

Bauer Peter O, Matoska Vaclav, Zumrova Alena, Boday Arpad, Doi Hiroshi, Marikova Tatana, Goetz Petr

机构信息

Neurogenetic Centre, Institute of Biology and Medical Genetics, Dept. of Child Neurology, Family Hospital Motol and 2nd Medical Faculty of Charles University, Prague, Czech Republic.

出版信息

J Appl Genet. 2005;46(3):325-8.

PMID:16110192

Abstract

We report on a family with spinocerebellar ataxia type 1 (SCA1), in which the age at onset and the severity of the disease do not correlate with the number of CAG repeat units. Although a marked anticipation was observed in the proband, it was not a consequence of an expansion of the CAG tract. None of the expanded alleles contained CAT interruptions. The pathologic expansion in this family was stable during the paternal but not maternal transmission, where it expanded by one trinucleotide and unexpectedly did not lead to anticipation. Our observations suggest that factors other than the length of the CAG repeat play a considerable role in determination of the disease course.

摘要

我们报告了一个患有1型脊髓小脑共济失调（SCA1）的家系，其中发病年龄和疾病严重程度与CAG重复单位的数量无关。尽管在先证者中观察到明显的遗传早现现象，但这并非CAG序列扩增的结果。所有扩增的等位基因均未包含CAT中断。该家系中的病理性扩增在父系传递过程中是稳定的，但在母系传递过程中不稳定，在此过程中它扩增了一个三核苷酸，且意外地未导致遗传早现。我们的观察结果表明，除CAG重复长度外的其他因素在疾病进程的决定中起着相当重要的作用。