If the number of people with each phenotype of a two allele system is known, then the gene frequency for each of the two alleles can be calculated.
|
Individual |
X Genes |
X[a] |
X[b] |
X(a+b-) |
c |
2 * c |
2 * c |
0 |
X(a+b+) |
d |
2 * d |
d |
d |
X(a-b+) |
e |
2 * e |
0 |
2 * e |
|
|
|
|
|
Totals |
c+d+e |
2 * (c+d+e) |
(2 * c) + d |
d + (2 * e) |
frequency of allele X[a] =
= ((2 * c) + d) / (2 * (c+d+e))
frequency of allele X[b] =
= (d + (2 * e)) / (2 * (c+d+e))
Specialty: Genetics