Question

In a population of gerbils, long hair (H) is completely dominant over short hair (h). If 18% of the population has short hair, calculate the percentage of the population that is expected to be heterozygous (Hh).

Answer 1

long hair = P
Short hair = q using the Hardy-Weinberg equation for genotypic frequencies \[p ^{2}+2pq+q ^{2}=1\]
First use the equation to solve for the known value 18% hh
\[.18 = q ^{2}\]
\[\sqrt{.18}=q\]
so q =.42
plug this allelic frequency into p+q = 1
which will give you the frequency of dominant alleles
1-.42 = p so p = .58
then just plug the p and q values found into the portion of the equation for heterozygous offspring.
2 (.58)(.42)
which comes out to about .49 or 49%
the entire population should be
33% homozygous dominant 49% heterozygous and 18% homozygous recessive

Assuming I did the math right you may want to double check me.

Answer 2

thank you that helped a lot :)

Answer 3

Glad I could help! Thanks for the medal :)

Answer 4

that was right? @andrea95