Fitzgerald P H, Archer S A, Morris C M
Hum Genet. 1986 Jan;72(1):58-62. doi: 10.1007/BF00278818.
A clinically normal 28-year-old woman had three conceptuses with trisomy 21 and one normal child. She showed minimal cytogenetic evidence of mosaicism: 4% of her blood cells and 6% of skin fibroblasts had trisomy 21. Also, 7% of her blood cells showed aneuploidy of the X chromosome which was associated with premature centromere division (PCD,X); 6% of fibroblasts showed trisomy 18, 10% of fibroblasts showed PCD,21, and 1% PCD,18. It is unlikely that this woman is a constitutional mosaic for trisomies X, 18, and 21, all at low levels. We suggest that she has a predisposition to irregular centromere separation and that chromosomes X, 18, and 21 are most susceptible to its action.
一名28岁临床检查正常的女性生育了三个21三体综合征胎儿和一个正常孩子。她仅有极少量的嵌合细胞遗传学证据：其血细胞的4%和皮肤成纤维细胞的6%存在21三体。此外，其7%的血细胞显示X染色体非整倍体，这与着丝粒过早分裂（PCD，X）有关；6%的成纤维细胞显示18三体，10%的成纤维细胞显示PCD，21，1%显示PCD，18。该女性不太可能是X、18和21三体的体质性嵌合体，且这些三体水平均较低。我们认为她有不规则着丝粒分离的易感性，而X、18和21号染色体最易受其影响。
