166k views
5 votes
Why is it that a P male and P female/M male and P female cross will not result in hybrid dysgenesis?

User Hatatister
by
7.3k points

1 Answer

4 votes

Final answer:

Hybrid dysgenesis doesn't occur in the mentioned fruit fly crosses because the P element causing genetic instability is not present in the female parent. F1 and F2 genotypes show red or white eyes depending on which P parent exhibits the recessive trait, with red being dominant.

Step-by-step explanation:

In the context of Drosophila melanogaster, or fruit flies, hybrid dysgenesis does not occur in a cross between P male (P element absent) and P female or M male (P element present) and P female because the P element that causes genetic instability is missing in the female parent. The phenomenon of hybrid dysgenesis is observed when P elements are introduced into the Drosophila genome through the male parent in crosses with M females, which lack these elements.

Regarding eye color, an X-linked trait, the F1 and F2 genotypes vary depending on whether the P generation male or female expressed the recessive white-eye trait. If the P male is white-eyed and the P female red-eyed, all F1 progeny will have red eyes due to the dominance of the red eye allele.

User Ammar Bukhari
by
7.6k points