In Europe, the frequency of the allele causing cystic fibrosis, cf , is about 0.
ID: 41570 • Letter: I
Question
In Europe, the frequency of the allele causing cystic fibrosis, cf, is about 0.04. Until 20 years ago, cystic fibrosis caused death before the age of 20.
a) Given the selection coefficient you calculated above, and assuming the population is in H-W equilibrium, what is the likely values of for the mutation from cf+to cf?
b) That is a ridiculously high mutation rate! Assume the heterozygote gets some kind of advantage (like the sickle cell carrier) and is the most fit genotype. The selection coefficient you calculated in a above is s2. Calculate the selection coefficient (s1) against the homozygous cf+cf+ genotype.
Explanation / Answer
cystic fibrosis ; the allelic frequency q = 0.04 allelic frequency is the measure of all allels at that specific type., the allelic frequency for the other aelle p will be 0.06, considering population to be 0.10
hardy wein burg equation ;
p2 +2pq+q2 = [0.06]2 + 2.0.04*0.06+ [0.04]2 =0.0036+0.0048+0.0016 = 0.008
selection coefficinet is the relative fitness of the genotype .
s=1-w = 1-0.008= 0.992 , so the s valve is very close to 0.1 it show s that it is lethal gene