1:49 minutes
Open Question
Another cross in Drosophila involved the recessive, X-linked genes yellow (y), white (w), and cut (ct). A yellow-bodied, white-eyed female with normal wings was crossed to a male whose eyes and body were normal but whose wings were cut. The F₁ females were wild type for all three traits, while the F₁ males expressed the yellow-body and white-eye traits. The cross was carried to an F₂ progeny, and only male offspring were tallied. On the basis of the data shown here, a genetic map was constructed.Phenotype Male Offspringy + ct 9+ w + 6y w ct 90+ + + 95+ + ct 424y w + 376y + + 0+ w ct 0Were any double-crossover offspring expected?
