A man is a known heterozygous carrier of a mutation that causes hemochromatosis (autosomal recessive disease). Suppose that 1% of the general population consists of homozygotes for this mutation. If the man mates with somebody from the general population, what is the best
estimate for the probability that he and his mate will produce a child who is an affected homozygote?
A. .025
B. .05
C. .09
D. .10
E. .25
sorry... dont know.
hardy weinberg... err... p2+2pq+q2...
dont you just hate that guy.. :O)
if i really had to guess id say. A.
IT`S ACTUALLY 2 GUYS...and yea...i never got the faintest idea what bothered them so much..gay couple in all probability
The correct answer is B. One must first determine the probability that the man's mate will also be a heterozygous carrier. This is done by applying the Hardy-Weinberg rule (p2 +2pq +q2> =1, where p2 is the frequency of homozygous dominant individuals, 2pq is the frequency of heterozygous individuals, and q2 is the frequency of homozygous recessive individuals). If the frequency of affected homozygotes is 1%, then the gene frequency of the hemochromatosis mutation is the square root of 1%, or 0.10. Then, the estimated frequency of heterozygous carriers in the population, 2pq, is 2 x 0.9 x 0.1 = 0.18 (notice that we do not use the 2q approximation in this case because p is not approximately equal to 1). The probability that two heterozygous carriers will produce an affected offspring is 0.25, so the probability that the man mates with a carrier and the probability that they will in turn produce an affected offspring is obtained by multiplying the two probabilities together: 0.25 x 0.18 = 0.045. Additionally, there is a small chance (0.01) that the person he mates with will be a homozygote, and thus there is a chance (0.01/2) that the offspring
of this mating will be affected, since the man has a 1 in 2 chance of transmitting the hemochromatosis gene. The correct answer, then, is 0.045+0.005 = 0.05.
common on... jajaja... that's soooooooooo unfair. !
great one !
can`t we just leave that man alone?
i know... i wanted to give last min. info... to u and bergkamp
thanks for the info... hope i dont get that question!