对一个罗氏易位家系中精子染色体分离和相互效应的研究

Analysis of meiotic segregation patterns and interchromosomal effects in sperm from a Robertsonian translocation family

目的研究罗氏易位个体精子中的染色体分离和染色体相互效应情况。方法采用荧光原位杂交技术精子标本进行间期核的原位杂交,并统计不同染色体分离方式的精子所占比例以及14,15,18,X和Y染色体的非整倍体比率。结果对于本文中的罗氏易位杂合子,其染色体正常和染色体平衡易位(对位分离)精子占79.9%,遗传物质不平衡(邻位分离)的精子占20.1%;并观察到高频率的性染色体非整倍体现象。对于本文中的罗氏易位纯合子,其染色体平衡易位精子占99.7%,遗传物质不平衡的精子占0.3%;未观察到高频率的性染色体非整倍体现象。结论罗氏易位杂合子的精子中染色体正常和染色体平衡易位(对位分离)的精子占有数量优势,且存在染色体相互效应。罗氏易位纯合子可正常产生22条染色体的遗传物质平衡的配子。

Objective： To provide more genetic information about meiotic segregation behavior and the possibility of interchromosomal effects （ICE） in spermatozoa from carders of Robertsonian （Rob） translocation. Methods： Analysis of sperm chromosomes by fluorescence in situ hybridization （FISH） . Frequencies of meiotic segregation products in sperm and sperm aneuploidy of chromosomes 14, 15, 18, X, and Y. Results： To Rob translocation heterozygote of this paper, the rate of normal/balanced spermatozoa resulting from alternate segregation is 79.9%. The frequency of unbalanced spermatozoa resulting from adjacent segregation is 20.1%. The higher frequencies of aneuploidy for sex chromosome were observed. To Rob translocation homozygosity, the rate of balanced spermatozoa is 99.7%. The frequency of unbalanced spermatozoa is 0.3%. The higher frequencies of aneuploidy for sex chromosome were not observed. Conclusion： Alternate segregation is dominant in the different types of Rob translocations. Carders may be at an increased risk for ICE. Rob translocation homozygosity could be seen as a potential speciation in humans with 44 chromosomes.