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    A human trait involving finger length in humans is recessive in males but dominant in females (This is true!). A survey of 938 college students found that 385 of 438 males and 104 of 500 females had dominant phenotypes. What are the allele frequencies?

    Here is my working and logic.

    Since the dominant phenotype is based on recessive alleles in males, this means the number of males who have the dominant alleles will be the ones not showing the trait, i.e. 438-385 = 53.

    This means that the total for dominance will be 53 + 104 = 157, out of 938.

    (157/938)^0.5 is p, hence q is 1 - that.

    I have no markscheme, so that's why I am asking for help. There was a Yahoo answer, but the gentlemen didn't consider the statement regarding the masking in the question.
 
 
 
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