Kohn P H, Whang-Peng J, Levis W R
Cancer Genet Cytogenet. 1982 Aug;6(4):289-302. doi: 10.1016/0165-4608(82)90085-1.
We have examined various aspects of lymphocyte chromosomal instability in three families comprised of five individuals affected with ataxiatelangiectasia (AT), their obligate heterozygous parents, and their unaffected sibs. We found that neither baseline sister chromatid exchanges (SCEs) nor mitomycin-C-induced increments in SCEs showed any significant differences among family members or between AT heterozygotes or homozygotes. Chromosome breakage in first-division metaphases was found to be moderately elevated in three of the five AT homozygotes (range 1-12%); breakage in the six AT obligate heterozygotes was within normal limits (0-4%). Analysis of Giemsa-banded metaphases indicated the presence of a clone bearing a paracentric inversion of chromosome #14 in addition to other chromosome #14 abnormalities in one AT homozygote. The same inversion was also found in this individual's affected sister and his obligate heterozygous father. A discussion regarding the relationship of the specificity of breakage and reunion of bands q12 and q23 on chromosome #14 and the high incidence of malignancy in AT is included.
我们研究了三个患有共济失调毛细血管扩张症（AT）的家庭中淋巴细胞染色体不稳定性的各个方面，这三个家庭包括五个患病个体、他们必然为杂合子的父母以及未患病的同胞。我们发现，无论是基线姐妹染色单体交换（SCE）还是丝裂霉素C诱导的SCE增加，在家庭成员之间、AT杂合子或纯合子之间均未显示出任何显著差异。在五个AT纯合子中有三个的第一次分裂中期染色体断裂中度升高（范围为1%-12%）；六个AT必然杂合子的断裂在正常范围内（0%-4%）。吉姆萨带型中期分析表明，除了一个AT纯合子中14号染色体的其他异常外，还存在一个带有14号染色体臂间倒位的克隆。在该个体患病的姐姐及其必然为杂合子的父亲中也发现了相同的倒位。文中还讨论了14号染色体上q12和q23带的断裂和重连特异性与AT中高恶性肿瘤发生率之间的关系。
