HardyWeinberg Principle Concepts and Equations HardyWeinberg Principle Population
Hardy-Weinberg Principle Concepts and Equations
Hardy-Weinberg Principle � Population genetics - study of properties of genes in populations � blending inheritance phenotypically intermediate (phenotypic inheritance) was widely accepted new genetic variants would quickly be diluted
Hardy-Weinberg Principle � Hardy-Weinberg - original proportions of genotypes in a population will remain constant from generation to generation � Sexual reproduction (meiosis and fertilization) alone will not change allelic (genotypic) proportions.
Hardy-Weinberg Equilibrium Population of cats n=100 16 white and 84 black bb = white B_ = black Can we figure out the allelic frequencies of individuals BB and Bb?
Hardy-Weinberg Principle � Necessary assumptions Allelic frequencies would remain constant if… � population size is very large � random mating � no mutation � no gene input from external sources � no selection occurring
Hardy-Weinberg Principle � Calculate genotype frequencies with a binomial expansion (p+q)2 = p 2 + 2 pq + q 2 � p 2 = individuals homozygous for first allele 2 pq = individuals heterozygous for alleles q 2 = individuals homozygous for second allele � �
Hardy-Weinberg Principle p 2 + 2 pq + q 2 and p+q = 1 (always two alleles) � � � � 16 cats white = 16 bb then (q 2 = 0. 16) This we know we can see and count!!!!! If p + q = 1 then we can calculate p from q 2 Q = square root of q 2 = q √. 16 q=0. 4 p + q = 1 then p =. 6 (. 6 +. 4 = 1) P 2 =. 36 All we need now are those that are heterozygous (2 pq) (2 x. 6 x. 4)=0. 48. 36 +. 48 +. 16
Hardy-Weinberg Equilibrium
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