Question

4. The Hardy-Weinberg Principle. For a single locus, if the frequency of one allele (allele A) is 0.4, the frequency of the other allele (allele B) is 0.6, what are the expected frequencies of the AA genotype, the AB genotype and the BB genotype in the next generation? What are the eight assumptions that should be met when making the genotype frequency predictions? How do the eight assumptions serve to form a null model for evolution? Finally, how does one use the model to test whether their population has evolved with this famous null model?

Answer 1

Hardy weinberg principle . Says if gene have 2 alleles A and a and if p is the frequency of occurence of dominant allele A, and q is the freq of occurence of recesseive allele ' a' in the parental generation. Then the genotype frequencies expected in offspring as per hardy weinberg equation

. 2 2 2

(P+q) = P   + q +2Pq=1

Given p=0.4

and q = 0.6

2

Frequency of AA genotype is. =P = 0.4×0.4= 0.16

Frequency of AB genotype is 2pq

2 × 0.4×0.6= 0.48

2

Frequency of BB genotype= q

0.6×0.6= 0.36

Total freq of 3 genotypes = 0.16+0.48+0.36= 1

Deviation is significant and the gene frequencies are changing and evolution is occuring.