Dominance and lethality of AY

 (a) A 1:1 ratio identifies AY as a dominant mutant allele. (b) The recessive lethality of AY in the homozygous genotype results in a 2:1 ratio of yellow to agouti in the cross of yellow-coated heterozygous mice (a) A 1:1 ratio identifies AY as a dominant mutant allele. (b) The recessive lethality of AY in the homozygous genotype results in a 2:1 ratio of yellow to agouti in the cross of yellow-coated heterozygous mice

(a) P ”Q x Q P w; x ' "‘4 AA . AAY Agoutl Yellow ¢—‘—¢ (“w %AA Agouti (a %AA Agouti \ 1 . ..w -AAYYe||ow -1 £7 2 _@»%AAY Yellow