Molecular cytogenetic study of sperm in men of translocation carrier

1.本文研究了一名45，XY，+der（14 ; 21）（q10 ; q10）男性精子的3，9，14，17，18和21号染色体的减数分裂分离。用染色体特异性DNA探针（D3 Z1、D9 Z5、D14 S308、D17 Z1、D18 Z1和D21 S65）进行双色FISH。精子有（21/21/14）、（21/14 14）、（21/-）、（-/14）信号的频率分别为2.3%、3.3%、2.6%、3.4%，高于对照组，低于理论频率（16.7%）。精子平衡率为88.3%，低于对照组。在3、9、17和18号染色体上，RT携带者的二体精子频率与对照组相当。这些数据表明，在染色体分离期间或之后存在一些选择，没有证据表明对RT携带者中的其他非倍性的染色体间效应。采用三种DNA探针[CEP 3、CEP 9和Tel 3q]和[D18 Zq、DXZ 1和DYZ 1]对一名46，XY，t（3 ; 9）（q26.2 ; q32）相互易位携带者杂合子男性精子进行了分子细胞遗传学分析。交替分离、相邻1分离、相邻2分离和3：1分离率分别为52.5%、35.9%、5.44%、5.93%，对照组精子分离率为98.7%，18二体、XX二体、XY二体、YY二体、而携带者的二倍体精子数与对照组无显著差异，表明约50%的精子是由不平衡分离产生的，相互易位携带者的减数分裂分离不存在染色体间效应。

1. Meiotic segregation of chromosomes 3,9,14,17,18 and 21 was stdied in sperm from a man of 45, XY,+der (14 ; 21) (q10 ; q10). Two -color FISH was performed with chromosome specif DNA probes (D3Z1, D9Z5, D14S308, D17Z1, D18Z1 and D21S65). The frequencies of sperm having (21 21/14), (21/14 14), (21/-), (-/14) signals were 2.3%, 3.3%, 2.6%, 3.4% respectively which were higher thatn those of control men and lower than those of theoretical frequency (16.7%). The frequency of sperm balanced was 88.3% which was lower than those of control men. For chromosome 3,9,17 and 18, the frequencies of disomic sperm in the RT carrier were compalable to those of control men. These data indicate the there is some selection during or after mciotic segregation, with no evidence for an inter-chromosomal effect on other ancuploidy in the RT carrier.2. Molecular cytogenetic analysis was done with sperm from a man heterozygous for a 46, XY,t (3 ; 9) (q26.2 ; q32) reciprocal translocation carrier using three color FISH with three DNA probes [CEP3, CEP9, and Tel 3q] and [D18Zq, DXZ1 and DYZ1]. The frequencies of sperm resulting from alternate segregation, adjacent 1 segregation, adjacent 2 segregation, and 3 : 1 segregation were 52.5%, 35.9%, 5.44%, 5.93%, respectively in a carrier, and that of sperm with balanced segregation was 98.7% in a control man. The frequency of 18 disomy, XX disomy, XY disomy, YY disomy, and diploid sperm in the carrier was not significantly different from that in a control man. These data indicate that about 50% sperm are produced by unbalanced segration, and that there is no inter-chromosomal effect in the meiotic segregation of the reciprocal translocation carrier.