In humans, red blood cells have a number of proteins embedded in the cell membra
ID: 69632 • Letter: I
Question
In humans, red blood cells have a number of proteins embedded in the cell membrane. One type of protein, the Rh factor, is controlled by a single gene and is either present or missing from the red blood cells. If present, the individual has the Rh phenotype. If missing, the individual has the Rh– phenotype. Rh is the dominant to Rh–. Suppose that, in the Basque population, the frequency of the Rh– phenotype is 0.16. Using the Hardy–Weinberg equations, calculate the frequency of the Rh allele to at least two decimal places.
Explanation / Answer
Hardy and Weinberg also described all the possible genotypes for a gene with two alleles. The binomial expansion representing this is, p2 + 2pq + q2 = 1.0
Where,
p2 = proportion of homozygous dominant individuals
q2 = proportion of homozygous recessive individuals
2pq = proportion of heterozygotes.
Given that the frequency of Rh– phenotype (recessive) is 0.16, i.e. q2 = 0.16 or q = 0.4
As p+q = 1, the frequency of p or the frequency of the Rh allele = 1- 0.4 = 0.6