Meiotic drive is a phenomenon observed occasionally in which a heterozygous genotype does not produce a 1: 1 proportion of functional gametes, usually because one of the gametic types is not formed or fails to function. Suppose that an allele D shows meiotic drive such that heterozygous Dd genotypes form 3/4 D-bearing and 1/4 d-bearing functional gametes. What is the expected ratio of genotypes in the F2 generation of a monohybrid cross under the assumptions stipulated below? (Hint: Use Punnett squares.)
(a) The meiotic drive occurs equally in both sexes.
(b) The meiotic drive occurs only in females.