Question #92142

What is the Hardly-Weinberg equation and what do the element represent?

Expert's answer

The Hardy-Weinberg equation is the fundamental concept in population genetics (the study of genetics in a defined group). It is a mathematical equation describing the distribution and expression of **alleles **(forms of a gene) in a population, and it expresses the conditions under which allele frequencies are expected to change.

According to this equation:

*p* = the frequency of the dominant allele (represented here by *A*)

*q* = the frequency of the recessive allele (represented here by *a*)

For a population in genetic equilibrium:

*p* + *q* = 1.0 (The sum of the frequencies of both alleles is 100%.)

(*p* + *q*)2 = 1

so

*p*2 + 2*pq* + *q*2 = 1

The three terms of this binomial expansion indicate the frequencies of the three genotypes:

*p*2 = frequency of *AA* (homozygous dominant)

2*pq* = frequency of *Aa* (heterozygous)

*q*2 = frequency of *aa* (homozygous recessive)

## Comments

## Leave a comment