Mosaic: A position-effect variegation eye-color mutant in the mosquito Anopheles gambiae

The Mosaic (Mos) mutation, isolated in the F-1 of Co-60-irradiated mosquito es, confers variegated eye color to third and fourth instar larvae, pupae, and adults of the mosquito Anopheles gambiae, Mos is recessive in wild pink eye (p(+)) individuals, but is dominant and confers areas of wild-type pig ment in mutant pink eye backgrounds. Mos is located 14.4 cM from pink eye o n the X chromosome and is associated with a duplication of division 2B euch romatin that has been inserted into division 6 heterochromatin, Various com binations of Mos, pink eye alleles, and the autosomal mutation red eye were produced. In all cases, the darker pigmented regions of the eye in Mos ind ividuals show the phenotypic interactions expected if the phenotype of thos e regions is due to expression of a p(+) allele, Expression of Mos is suppr essed by rearing larvae at 32 degrees C relative to 22 degrees C, All of th ese characteristics are consistent with Mos being a duplicated wild copy of the pink eye gene undergoing position-effect variegation.