Dewees A A
J Hered. 1982 Sep-Oct;73(5):330-4. doi: 10.1093/oxfordjournals.jhered.a109663.
The analysis of the cosegregation of recombinant and sex chromosomes in D. melanogaster by Hiraizumi to determine time of origin of the male recombination event(s) has been extended to include a heterologous autosome. Recombination in F1 males was measured simultaneously in marked second and third chromosomes. The results of crosses of unrelated strains in two laboratories revealed a significant excess of pairs of like-recombinant flies in the same brood that also were of the same sex and of identical genotype for the marked heterologous autosome. This nonrandom association of three chromosome pairs following meiosis, coupled with a numerical analysis that yielded estimates of the average numbers of primary spermatocytes containing either meiotic or premeiotic exchanges, provides further evidence that a large proportion of male recombination can be explained by premeiotic exchange events. Because of the additional finding of small clusters of recombinants in the same brood, it is suggested that male recombination is due to exchange in spermatogonia one or two cell divisions prior to initiation of meiosis.
平泉对黑腹果蝇中重组染色体与性染色体的共分离进行分析，以确定雄性重组事件的起源时间，该分析已扩展到包括一条异源常染色体。在有标记的第二和第三条染色体中同时测量了F1雄性的重组情况。两个实验室中不相关品系杂交的结果显示，同一窝中具有相同重组类型的果蝇对显著过量，这些果蝇也是同性别的，并且对于有标记的异源常染色体具有相同的基因型。减数分裂后这三对染色体的这种非随机关联，再加上通过数值分析得出的含有减数分裂或减数分裂前交换的初级精母细胞平均数量的估计值，进一步证明了很大一部分雄性重组可以由减数分裂前的交换事件来解释。由于在同一窝中还发现了小的重组体簇，因此有人提出雄性重组是由于在减数分裂开始前一到两个细胞分裂周期的精原细胞中发生了交换。
