Hardy-Weinberg equilibrium principle /här″dē wīn″ bərg/ [G.H. Hardy, English mathematician, 1877–1947; Wilhelm Weinberg, German physician, 1862–1937; L, aequilibris, equal weight, principium, a beginning] , a principle stating that the frequency of alleles and genotypes remains relatively unchanged from generation to generation in a large, interbreeding population characterized by random mating, Mendelian inheritance, and the absence of migration, mutation, and selection. Under such conditions, the ratio of individuals homozygous for a dominant allele to those heterozygous to those homozygous for a recessive allele is 1:2:1. See also genetic equilibrium.
