Orr H A
Center for Population Biology, University of California, Davis 95616.
Genet Res. 1992 Apr;59(2):73-80. doi: 10.1017/s0016672300030275.
Almost nothing is known about the identity of the genes causing reproductive isolation between species. As a first step towards molecular isolation of a 'speciation gene', I mapped and partly characterized a gene causing hybrid male sterility in Drosophila. This analysis shows that sterility of D. melanogaster males who carry the 'dot' fourth chromosome from D. simulans is due entirely to a very small region of the D. simulans chromosome (including only about 5 salivary gland bands or approximately 250 kb of DNA). Thus the hybrid sterility effect of the D. simulans fourth chromosome is almost surely due to a single gene of very large effect (here named hms, hybrid male sterile). Hms is zygotically acting, and the D. simulans allele of hms is completely recessive. Furthermore, complementation tests suggest that hms is not an allele of any known locus in D. melanogaster.
关于导致物种间生殖隔离的基因的身份，我们几乎一无所知。作为朝着“物种形成基因”的分子分离迈出的第一步，我绘制了果蝇中一个导致杂种雄性不育的基因图谱并对其进行了部分特征描述。该分析表明，携带来自拟果蝇（D. simulans）的“点状”第四条染色体的黑腹果蝇（D. melanogaster）雄性的不育完全归因于拟果蝇染色体的一个非常小的区域（仅包括约5个唾液腺带或约250 kb的DNA）。因此，拟果蝇第四条染色体的杂种不育效应几乎肯定是由一个具有非常大效应的单一基因（此处命名为hms，杂种雄性不育）引起的。Hms是合子起作用的，并且hms的拟果蝇等位基因是完全隐性的。此外，互补试验表明hms不是黑腹果蝇中任何已知基因座的等位基因。
