title: Dominant-and-recessive epistasis in a homeotic mosquito mutant.
abstract: Following selection for 15 generations a pure strain of a homeotic mutant spur was isolated from a Brazilian population of the mosquito Culex pipiens fatigans. Monohybrid crosses showed a 13:3 segregation indicating dominant-and-recessive epistasis for wild-type vs. spur. This implies that a dominant allele at one locus and a recessive at the other interact to produce the mutant phenotype. Dihybrid crosses with linkage group II markers yellow and ruby gave 39:13:9:3 ratios indicating independent segregation. However, the dihybrid cross with linkage group I marker maroon showed a highly significant departure from 39:13:9:3 ratio. Data available indicate that the phenotype spur is controlled by a dominant epistat in linkage group III and a recessive epistat (approximately 31.9 crossover units from maroon) in linkage group I.
mesh_terms: D000483:Alleles; D000818:Animals; D003433:Crosses, Genetic; D003465:Culex / Q000033:anatomy & histology*; D005260:Female; D005799:Genes, Dominant; D005808:Genes, Recessive; D008040:Genetic Linkage; D008297:Male; D009154:Mutation; D010641:Phenotype