DuFrain R J, Littlefield L G, Morrison W D, Huff V D, Hutton D
Mutat Res. 1984 Jun;127(1):73-9. doi: 10.1016/0027-5107(84)90142-8.
The frequency of consistent structural chromosome aberrations was determined for 108 fetuses (day 14 of gestation) from 20 female rabbits treated before conception with 90 micrograms/kg of streptonigrin (NSC-45383). The findings by karyotype analysis of 1.85% of the fetuses with consistent aberrations was compared with 6.32% frequency previously observed in 6-day (preimplantation) blastocysts from identically treated females and found to be significantly reduced. The interpretation of the findings is that the developmental events of implantation and placentation are effective in eliminating from further gestation the majority of the rabbit conceptuses with consistent structural chromosome abnormalities. The data are also discussed relative to the predictive nature of somatic cell chromosome damage in women of childbearing age being an estimator of risk of producing offspring with structural chromosome aberrations. The data show that preconceptional treatment of female rabbits with streptonigrin caused a shift in the cytogenetically determined sex ratio of the 14-day fetuses, but not of the 6-day blastocysts. The significant decrease in relative numbers of males observed is consistent with the induction of lethal mutations on the X chromosome. This finding is discussed in conjunction with the timing and parental specificity of X chromosome inactivation during mammalian embryonic development.
对20只在受孕前用90微克/千克链黑菌素（NSC - 45383）处理过的雌性兔子所产的108只胎儿（妊娠第14天），测定了一致性结构染色体畸变的频率。对1.85%有一致性畸变的胎儿进行核型分析的结果，与之前在同样处理的雌性兔子的6天（着床前）囊胚中观察到的6.32%的频率进行了比较，发现显著降低。这些发现的解释是，着床和胎盘形成的发育事件有效地从进一步妊娠中消除了大多数具有一致性结构染色体异常的兔子胚胎。还讨论了这些数据与育龄妇女体细胞染色体损伤的预测性质之间的关系，体细胞染色体损伤可作为产生具有结构染色体畸变后代风险的一个估计指标。数据表明，受孕前用链黑菌素处理雌性兔子，导致14天胎儿的细胞遗传学确定的性别比例发生变化，但6天囊胚的性别比例未变。观察到的雄性相对数量的显著减少与X染色体上致死突变的诱导一致。结合哺乳动物胚胎发育过程中X染色体失活的时间和亲本特异性对这一发现进行了讨论。
