精子细胞的荧光原位杂交

Fluorence in situ hybridization in human ejaculated sperm

在新生儿中大约1／500出现染色体非整倍体（aneuploid）[1]，特别是在精子配子中其发生频率较高，是引起自然流产、婴儿死亡及神经系统发育迟缓的重要原因[2]。因而人类配子细胞已经成为筛查染色体非整倍体及估计染色体不分离发生的焦点之一。1970年Barlow等曾用阿的平对人类精子核Y染色体长臂染色，通过计数荧光信号判断Y染色体数目[3]，但由于非特异背景，两个Y的频率较高[4]。1978年Rudak首次描述了以“仓鼠穿卵法”制备精于染色体，并用来检测染色体数目及结构异常[5]。但方法复杂，技术难度大，并且只能对那些能穿透仓鼠卵细胞的精子进行分析，因而至今不能做一种常规的检测方法[6]。本文介绍一种简便而快速的检测精子染色体数目异常的方法，以D21Z1／D13Z1、TRX探针与精子问期核进行荧光原位杂交（fluorescenceinsituhybridization，FISH），能准确的计数精子核中染色体数目。

Chromosome aneuploidy occurs inapproximately l in 500 newborns. Aneuploidy mostoften arises in the germ cell and is a common causeof spontanous aborition, in fact death and mentalretardation. Human germ cells have thereforebecome the focus of study in screening foraneuploidy and estimating the occurrence ofnondisjunction in humans. In attempts to estimateaneuploidy, quinacrine staining of human spermdetected a bright fluorescence representing thedistal long arm of the Y chromosome (1970).However, this method incorrectly estimated thepercentage of sperm containing a Y chromosomeand overestimated the frequency of sperm with twoY chromosomes. Presently, the most informativemethod for the study of human sperm chromosomes is by in vitro fertilization of hamsteroccytes (1978). Though this method has currentlyprovided estimates of nondisjunction in sperm. Ithas not been established as a routine method due toexperimental complications and technicaldifficultes, In addition, only those sperm which arecapable of fusing with hamster occytes can beaccessed. Here, we introduce a simple method fordetecting aneuploidy in human ejaculated sperm.Using fluorescence in situ hybridization (FISH)with chromosome specifit for 21/13 and X DNAprobes, we can accurately detect numericalchromosome abnormalities in human sperm bycounting the number of fluorescent spots.