Presgraves D C, Orr H A
Department of Biology, University of Rochester, Rochester, NY 14627, USA.
Science. 1998 Oct 30;282(5390):952-4. doi: 10.1126/science.282.5390.952.
Haldane's rule states that species hybrids of the XY sex are preferentially sterile or inviable. In all taxa known to obey this rule, the Y is inert and X-linked genes show full expression in XY individuals. Until recently, all theories of Haldane's rule depended on this hemizygosity. A test of Haldane's rule in animals lacking a hemizygous sex-mosquitoes having two functional sex chromosomes in both sexes-reveals that these species show Haldane's rule for sterility but not inviability. A related group having a "normal" hemizygous X obeys Haldane's rule for both sterility and inviability. These results support the faster male and dominance theories of Haldane's rule.
霍尔丹法则指出，XY性别系统的物种杂交后代往往优先表现为不育或无法存活。在所有已知遵循这一法则的分类群中，Y染色体是无活性的，X连锁基因在XY个体中能完全表达。直到最近，所有关于霍尔丹法则的理论都依赖于这种半合子状态。在缺乏半合子性别的动物（雌雄两性都有两条功能性性染色体的蚊子）中对霍尔丹法则进行的一项测试表明，这些物种表现出了关于不育的霍尔丹法则，但没有表现出关于无法存活的法则。一个具有“正常”半合子X染色体的相关群体则同时遵循关于不育和无法存活的霍尔丹法则。这些结果支持了霍尔丹法则的快速雄性进化理论和显性理论。
