A molecular linkage map for Drosophila mediopunctata confirms synteny with Drosophila melanogaster and suggests a region that controls the variation in the number of abdominal spots

Abstract

The classic approach to gene discovery relies on the construction of linkage maps. We report the first molecular-based linkage map for Drosophila mediopunctata, a neotropical species of the tripunctata group. Eight hundred F(2) individuals were genotyped at 49 microsatellite loci, resulting in a map that is ≈450 centimorgans long. Five linkage groups were detected, and the species' chromosomes were identified through cross-references to BLASTn searches and Müller elements. Strong synteny was observed when compared with the Drosophila melanogaster chromosome arms, but little conservation in the gene order was seen. The incorporation of morphological data corresponding to the number of central abdominal spots on the map was consistent with the expected location of a genomic region responsible for the phenotype on the second chromosome.