In Drosophila, white eyes (w) are recessive to red eyes (w+) at one locus and black body (b) is recessive to gray body (b+). A homozygous white eyed, gray bodied female is crossed with a homozygous red eyed, black bodied male to produce the F1 progeny. The F1 progeny are testcrossed and produce the following progeny:

White eyes, black body 212

White eyes, gray body 288

Red eyes, black body 308

Red eyes, gray body 192


a. Does the evidence indicate that the w and b loci are linked? Explain your answer!


b. If they are linked, what is the map distance between the two loci? If they are not linked, what is the map distance between the two loci? If they are linked, are the alleles in the F1 in coupling or repulsion? How do you know?


c. Draw the genotypes of all individuals described in the problem (original parents, F1, testcross, and F2 progeny) using the appropriate notation.