The allele frequency or the gene frequency, represents the incidence of a gene variant in a population.

By measuring the amount of genetic variation in a population, scientists can begin to make predictions about how genetic variation changes over time.

**Formula to calculate allele frequency.**

**Example:**

Suppose the allele of interest is Z, calculate the allele frequency in a population of 600 animals we count 350 animals with the genotype Z/Z.

Therefore, the allele frequency is 0.583 or 58.3%.