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+--- Thread: Q. the frequency of homozygous - hunanliu (/showthread.php?tid=72671)
Q. the frequency of homozygous - hunanliu - ArchivalUser - 02-02-2006
In a Nigerian population, the frequency of males with G6PD deficiency is 0.2. Assuming the
population is in Hardy-Weinberg equilibrium at this locus, what is the frequency of homozygous
females?
/ A. 0.02
/ B. 0.04
/ C. 0.2
/ D. 0.32
/ E. 0.45
0 - ArchivalUser - 02-02-2006
Given that q=0.2, so q^2=0.04.
0 - ArchivalUser - 02-02-2006
hi calender you considered they are asking homozygous sick female right? what will the answer be if they mean homozygous female nl &sick?
0 - ArchivalUser - 02-02-2006
I thought they ask about homozygous mutation at that specific locus, don't they? That means, they are asking about frequency of diseased females.
0 - ArchivalUser - 02-02-2006
G6PD is an Xlinked recessive, so male is hemizygous for X chromosome. so male has only one copy of each trait, so the frequency of X linked recessive in males is equal to allel in the population. So q= 0.2 and p = 0.8. female has two copies of each geneon x chromosome, so equation for hardy weinberg equilibrium is same for autosomal traits. in this case homogygous recessive female would occur at a frequency of q square or 0.04.
0 - ArchivalUser - 02-03-2006
thanks calender,gl