Heterozygosity and Sex Determination in Haplo-Diploidy

作者：Ross H. Crozier · 发表于：The American Naturalist · 年份：1971 · DOI：10.1086/282733 · 被引用次数：218 · 研究领域：Insect-Plant Interactions and Control、Genetic and Clinical Aspects of Sex Determination and Chromosomal Abnormalities、Insect and Pesticide Research

Sex determination in haplo-diploid animals has been explained by P. W. Whiting's (1939) single-locus, multiple-allele scheme, which is applicable to two cases only, or by da Cunha and Kerr's (1957) genic-balance scheme, a more general hypothesis. I propose a general hypothesis of sex determination in haplo-diploidy, based on Snell's (1935) multiple-factor suggestion. This multiple-locus hypothesis is that, in haplo-diploid species, sex is determined by a number of loci. Females are heterozygous at one or more loci, while males are homozygous or hemizygous at all sex loci. At the molecular level, this effect might be due to female-determining properties of heteropolymers formed betwen the products of different alleles at any sex locus; homopolymers or heteropolymers between products of different loci are not formed or lack sex-determining activity. Haploid intersexes could arise from mutants that form active homopolymers or active heteropolymers with products of other loci. Diploid intersexes should be extremely rare, except in single-locus species, in which intersexes could result from mutations that reduce heteropolymer formation. The data from a number of cases generally support the multiple-locus hypothesis for Hymenoptera and haplo-diploid mites but not for coccids. No suitable data exist for other haplo-diploid groups. Compared with single-locus species, those with many sex loci will have weaker selection operating on the alleles at each locus and will lose fewer diploid...