HARDY-WEINBERG LAW

Hardy-Weinberg law was discovered independently in 1908 by Wilhelm Weinberg, a German physician, and Godfrey Harold Hardy, a British mathematician.

The Hardy-Weinberg law states that,

"In a large, random-mating population, the genotype and allele frequencies remain constant in the absence of any evolutionary influences from one to another generation."

The conditions to maintain the Hardy-Weinberg equilibrium are: no mutation, no gene flow, large population size, random mating, and no natural selection. Because all of these disruptive forces commonly occur in nature, the Hardy-Weinberg equilibrium rarely applies in reality.

The Hardy-Weinberg formulas allow scientists to determine genetic equilibrium or whether evolution has occurred in a population. 

Two formulas must be memorized:

p2 + 2pq + q2 = 1 and p + q = 1

p = frequency of the dominant allele in the population

q = frequency of the recessive allele in the population

p2 = percentage of homozygous dominant individuals

q2 = percentage of homozygous recessive individuals

2pq = percentage of heterozygous individuals

Some of the major factors which affect the genetic equilibrium and induce the variability in a population are as follows: (A) Mutations (B) Recombinations during Sexual Reproduction (C) Genetic Drift (D) Gene Migration (Gene Flow) (E) Natural Selection.

This Will be explained in detail in upcoming posts

Applications:

Medical geneticists can use the Hardy-Weinberg law to calculate the probability of human matings that may result in defective offspring. The law is also useful in determining whether the number of harmful mutations in a population is increasing as a result of radiation from industrial processes, medical techniques, and fallout.