Guttenbach M, Koschorz B, Bernthaler U, Grimm T, Schmid M
Institut für Humangenetik, Universität Würzburg, Germany.
Am J Hum Genet. 1995 Nov;57(5):1143-50.
A total of 1,000 lymphocyte interphase nuclei per proband from 90 females and 138 males age 1 wk to 93 years were analyzed by in situ hybridization for loss of the X and Y chromosomes, respectively. Both sex chromosomes showed an age-dependent loss. In males, Y hypoploidy was very low up to age 15 years (0.05%) but continuously increased to a frequency of 1.34% in men age 76-80 years. In females, the baseline level for X chromosome loss is much higher than that seen for the Y chromosome in males. Even prepubertal females show a rate of X chromosome loss, on the order of 1.5%-2.5%, rising to approximately 4.5%-5% in women older than 75 years. Dividing the female probands into three biological age groups on the basis of sex hormone function (< 13 years, 13-51 years, and > 51 years), a significant correlation of X chromosome loss versus age could clearly be demonstrated in women beyond age 51 years. Females age 51-91 years showed monosomy X at a rate from 3.2% to 5.1%. In contrast to sex chromosomal loss, the frequency of autosomal monosomies does not change during the course of aging: Chromosome 1 and chromosome 17 monosomic cells were found with a constant incidence of 1.2% and 1%, respectively. These data also indicate that autosome loss in interphase nuclei is not a function of chromosome size.
对90名女性和138名年龄从1周大到93岁的男性先证者，分别通过原位杂交分析了每个先证者共1000个淋巴细胞间期核，以检测X和Y染色体的缺失情况。两条性染色体均显示出与年龄相关的缺失。在男性中，直到15岁，Y染色体亚二倍体率非常低（0.05%），但在76 - 80岁的男性中持续增加至1.34%。在女性中，X染色体缺失的基线水平远高于男性Y染色体的基线水平。即使是青春期前的女性也显示出X染色体缺失率，约为1.5% - 2.5%，在75岁以上的女性中升至约4.5% - 5%。根据性激素功能将女性先证者分为三个生物学年龄组（<13岁、13 - 51岁和>51岁），51岁以上女性的X染色体缺失与年龄之间存在显著相关性。51 - 91岁的女性显示单体X的发生率为3.2%至5.1%。与性染色体缺失不同，常染色体单体的频率在衰老过程中不会改变：分别发现1号染色体和17号染色体单体细胞的发生率恒定为1.2%和1%。这些数据还表明，间期核中常染色体的缺失不是染色体大小的函数。
