【摘要】 鲫鱼二倍体染色体数目为2n=100。应用BrdU-Hoechst 33258-Giemsa技术及C带技术研究表明,鲫鱼性别决定为XY型。B₂染色体可能是性染色体,其短臂（B₂-P区）是与性别决定有关的区域,是晚复制的,是C带区。在复制行为及C带分布上均出现与性别相关的规律性表现。在复制晚期阶段,雌性个体的该区域是同步复制的;雄性个体的该区域则是异步复制的。在C带分布上,雌性两个该区域均为C带深染,雄性则只有一个呈深染,另一个则呈浅染。更多还原

【Abstract】 The time sequences of DNA replication in the chromosomes of 2 male and 3 female common earps were studied by a modified BrdU-Hoechst 33258-Giemsa technique, using the asynchronized cultivated lymphocytes and kidney cells in vitro. It was found that the sex determination of Carassius auratus was of XX/XY type, chromosome pair No. 2 in B group was probably the sex chromosome, of which the short arms were the latest in the replication in karyotype of all observed individuals. We called the regions B2-P. The two B2-P replicated synchronously in female animals, but asynchronously in male. The replicative hetermorphism occurred in late S phase. The above-mentioned regions were C-banding dark staining both in female and one dark but another bright in male.更多还原