A copy of the copia transposable element is very tightly linked to the w^a allele at the white locus of D. melanogaster

Results are described demonstrating that several X chromosomes of Drosophila melanogaster carrying the w^a (white-apricot) mutant allele also carry homology to the copia transposable element in distal 3C of the polytene chromosome map as assessed by in situ hybridization. The locus of the w^a mutation, white, resides in distal 3C. We further show, using fine scale genetic mapping techniques, that the copia homology in distal 3C in w^a-bearing chromosomes is very tightly linked to the w^a mutation. Both the w^a mutation and the copia homology associated with it map to the central portion of the white locus.