Question

Hemophilia is a gender-linked blood disorder in humans. The gene responsible for it is gene-linked recessive, meaning it is present on the X chromosome. When the gene is present in males (Xh), it always expresses itself, meaning that the male's blood won't clot properly. When present in females in a heterozygous condition (XhXH), the gene doesn’t express itself; but the female becomes a carrier, meaning that her offspring could have hemophilia.. When present in a homozygous recessive condition in females (XhXh), it expresses itself. One of every 10,000 persons is affected by this disease. What could be the allele frequency for this disease in the entire population?

Answer 1

A. Since thin fur is recessive, the odds of having thin fur are the odds that an allele codes for thin fur, squared. The odds of thin fur are 49/540. The square root of 49/540 is roughly 7/23, making the frequency of c roughly 7/23 and C roughly 16/23.

Answer 2

If 1 of 10,000 persons is affected, q2 = 1/10000 = 0.0001

The frequency of hemophilia allele is q = 0.01

p + q = 1, so p = 1 – 0.01 = 0.99

The frequencies of alleles for hemophilia are p = 0.99, and q = 0.01, where p is the negative allele for hemophilia, and q is the positive allele for hemophilia