在女性,C组染色体缺失的细胞比例随年龄而增加;而且,减数分裂不分离的频率也随母龄增长而增高。在男性,不分离的发生也可能随年龄增长而增高。 1974年,Eiberg描述了一种Cd显带技术,可以在着丝粒两端染出两个小暗点,Cd代表着丝粒点。后来发现,活性着丝粒和失活着丝粒对于C带技术都是阳性的,但只有前者对Cd显带是阳性的。本文应用Cd显带技术研究老年妇女的有丝分裂相,作者发现,Cd-阴性染色体的 In women, the proportion of cells missing in group C increases with age, and the frequency of non-segregation of meiosis also increases with age. In men, the occurrence of non-separation may also increase with age. In 1974, Eiberg described a Cd banding technique that dyed two small dark spots at each end of a centromere, with Cd representing the centromere. Later, both active and inactive centromeres were found to be positive for C-band technology, but only the former was positive for Cd banding. In this paper, the use of Cd-banding technology to study the mitosis of elderly women, the authors found that Cd-negative chromosome