The Hardy-Weinberg equation used to determine genotype frequencies is: p2 + 2pq + q2 = 1. Where ‘p2’ represents the frequency of the homozygous dominant genotype (AA), ‘2pq’ the frequency of the heterozygous genotype (Aa) and ‘q2’ the frequency of the homozygous recessive genotype (aa).
What are the two equations for Hardy-Weinberg?
Since p = 1 – q and q is known, it is possible to calculate p as well. Knowing p and q, it is a simple matter to plug these values into the Hardy-Weinberg equation (p² + 2pq + q² = 1). This then provides the predicted frequencies of all three genotypes for the selected trait within the population.
What is P and Q biology?
In the simplest system, with two alleles of the same locus (e.g. A,a), we use the symbol p to represent the frequency of the dominant allele within the population, and q for the frequency of the recessive allele.
What does the 2 in 2pq mean?
Explanation: In the Hardy-Weinberg equilibrium equation ( p2+2pq+q2=1 ), the term 2pq represents the genotype frequency of heterozygotes (Aa) in a population in equilibrium. The term p2 represents the frequency of dominant homozygotes (AA) and the term q2 represents the frequency of recessive homozygotes (aa).
Why does the Hardy-Weinberg equation equal 1?
Determining the allele frequency
The first Hardy-Weinberg equation (p + q = 1) concerns estimating the frequency of alleles in a population. Each gene usually has two alleles (diploid organism), one from each parent. These alleles are denoted as the dominant (A) and recessive (a) forms.
What is Q 2 Hardy-Weinberg?
In the equation, p2 represents the frequency of the homozygous genotype AA, q2 represents the frequency of the homozygous genotype aa, and 2pq represents the frequency of the heterozygous genotype Aa. In addition, the sum of the allele frequencies for all the alleles at the locus must be 1, so p + q = 1.
What is meant by an allele?
An allele is one of two or more versions of a gene. An individual inherits two alleles for each gene, one from each parent. … Though the term allele was originally used to describe variation among genes, it now also refers to variation among non-coding DNA sequences.
Is a gene a pool?
A gene pool is the total genetic diversity found within a population or a species. … Inbreeding contributes to the creation of a small gene pool and makes populations or species more likely to go extinct when faced with some type of stress.
Why is there a 2 in 2pq but not in p2 or q2?
9. Why is there a “2” in “2pq” but not in “p2” nor “q2”? 16% of a population is unable to taste the chemical PTC. These non- tasters are recessive for the tasting gene.
What does 2pq equal?
Answer: The frequency of heterozygous individuals is equal to 2pq. In this case, 2pq equals 0.32, which means that the frequency of individuals heterozygous for this gene is equal to 32% (i.e. 2 (0.8)(0.2) = 0.32).
Why is 2pq not PQ?
Note that the heterozygotes are not 2pq but pq because in each case they are only being considered for the one allele in question. If we scale all wii’s such that the largest = 1.0 we refer to these as the relative fitnesses of the genotypes. A worked example where p = . 4, q = .
What does P Q 1 mean?
p + q = 1. describes allele frequencies for a gene with two alleles. (This is the simplest case, but the equation can also be modified and used in cases with three or more alleles.) If we know the frequency of one allele (p) we can easily calculate the frequency of the other allele (q) by 1 ó p = q.
Is P Q 1 always true?
The frequency of the a allele (q) = the number of a alleles (60) divided by the total number of alleles (200). Notice that p and q sum to 1 -> 0.7 + 0.3 = 1. This is always true if there are only two alleles. A good check on your math is to calculate these independently of each other and check that they sum to 1.
What are the 5 conditions of the Hardy-Weinberg principle?
The conditions to maintain the Hardy-Weinberg equilibrium are: no mutation, no gene flow, large population size, random mating, and no natural selection. The Hardy-Weinberg equilibrium can be disrupted by deviations from any of its five main underlying conditions.