Institut Jacques Monod, Université Paris Diderot, Paris, France.
Université Paris-Diderot, Paris, France.
Eur J Hum Genet. 2018 Dec;26(12):1875-1878. doi: 10.1038/s41431-018-0225-0. Epub 2018 Aug 10.
Increasing levels of aneuploidy of the sex chromosomes in human lymphocytes with age have been noted for several decades. The percentage of chromosome Y loss can reach up to 1.5% or even more, whereas the levels of X0 cells in females can increase up to 5% with age. Here, I propose simple mathematical models of the dynamics of 'normal' sex chromosome loss with age. These exponential models provide more mechanistic insights than linear regressions. They account for the lower incidence of sex chromosome loss in young individuals and its increase with age. Moreover, the exponential models show that aneuploidy of the sex chromosomes provides a selective advantage. As there are no longitudinal data available (for the same individual at different time points), the parameters reported here are average values derived from a population. Hopefully, this study will stimulate further work based on next-generation technologies to obtain better estimates of sex chromosome aneuploidy and of the parameters of the models discussed here.
几十年来，人们已经注意到人类淋巴细胞中性染色体非整倍体水平随年龄的增长而增加。染色体 Y 的丢失率可达 1.5%甚至更高，而女性 X0 细胞的水平随年龄的增长可增加到 5%。在这里，我提出了“正常”性染色体随年龄丢失的动力学的简单数学模型。这些指数模型比线性回归提供了更具机制性的见解。它们解释了年轻个体中性染色体丢失发生率较低，以及随年龄增长而增加的原因。此外，指数模型表明性染色体非整倍体提供了选择优势。由于目前尚无（在不同时间点对同一个体）纵向数据，因此此处报告的参数是从人群中得出的平均值。希望这项研究将激发基于下一代技术的进一步工作，以获得更好的性染色体非整倍体估计值和本文讨论模型的参数。
