Meyn M S
Department of Genetics, Yale University School of Medicine, New Haven, CT 06510.
Science. 1993 May 28;260(5112):1327-30. doi: 10.1126/science.8493577.
Ataxia-telangiectasia (A-T) is an inherited human disease associated with neurologic degeneration, immune dysfunction, and high cancer risk. It has been proposed that the underlying abnormality in A-T is a defect in genetic recombination that interferes with immune gene rearrangements and the repair of DNA damage. Recombination was studied in A-T and control human fibroblast lines by means of two recombination vectors. Unexpectedly, spontaneous intrachromosomal recombination rates were 30 to 200 times higher in A-T fibroblast lines than in normal cells, whereas extrachromosomal recombination frequencies were near normal. Increased recombination is thus a component of genetic instability in A-T and may contribute to the cancer risk seen in A-T patients.
共济失调毛细血管扩张症（A-T）是一种与神经退行性变、免疫功能障碍和高癌症风险相关的人类遗传性疾病。有人提出，A-T的潜在异常是基因重组缺陷，这会干扰免疫基因重排和DNA损伤修复。通过两种重组载体对A-T和对照人成纤维细胞系中的重组进行了研究。出乎意料的是，A-T成纤维细胞系中的自发染色体内重组率比正常细胞高30至200倍，而染色体外重组频率接近正常。因此，重组增加是A-T基因不稳定的一个组成部分，可能导致A-T患者出现癌症风险。
