Suppose you discovered a new mutation in mice that causes a curved spine.You noticed that this mutant phenotype is present only in females.When curved-spine females are crossed with normal males, the progeny are always recovered in a 1:1:1 ratio of curved-spine females, normal females, and normal males.Explain the genetic basis for this ratio.
A)hemizygous or homozygous lethal autosomal allele
B)hemizygous or homozygous lethal sex-linked allele
C)recessive sex-linked allele
D)recessive autosomal allele
E)dominant sex-linked allele

Question

Quizplus · Accepted Answer

The observed 1:1:1 ratio of curved-spine females, normal females, and normal males suggests a sex-linked inheritance pattern, specifically on the X chromosome. The absence of curved-spine males indicates that the allele causing the curved spine might be lethal when hemizygous in males (who have only one X chromosome) or homozygous in females. This pattern is consistent with a hemizygous or homozygous lethal sex-linked allele.

Suppose You Discovered a New Mutation in Mice That Causes