Have a good PPT link: https://max.book118.com/html/2017/0319/96003245.shtm
Population genetics, often mentioned among groups of random mating, random mating is an important prerequisite for Hardy-Weinberg law;
In practice, however, inbreeding among populations often occur, particularly in plant population, the inbreeding in the population,
Mating relationship is not random, resulting in the proportion of the population increases homozygote, heterozygote ratio decreased;
Therefore, in order to measure the degree of inbreeding populations, inbreeding coefficient was born. Inbred populations degree of cross near the average inbreeding coefficient is a measure commonly used groups.
The average coefficient of inbreeding diploid refers to: a random sample from a population of two alleles carries the body of the probability of homologous.
Diploid assumed a population allele frequencies are A and p, q, average inbreeding coefficient is F,
a population of individuals carrying any pair of alleles must exist or homologous, the probability is F;
presence or iso source, with probability 1-F.
If the heterologous allele, the genotype frequencies randomly mated populations the population is
genotype body;
if it is homologous allele, then there must be a homozygote of the genotype
(and other homologous the probability of a combination of alleles) is the population allele frequency
Next Generation genotype frequencies:
D’=p2(1-F)+pF
R’=q2(1-F)+qF
H’=2pq(1-F)
The next generation of allele frequencies:
p’=p2(1-F)+pF+pq(1-F)
=p
q = q2 (1 F) + FF + FP (1-F)
=q
If inbreeding F value of each generation plant population remains unchanged, the population allele frequencies.
Remain unchanged, the population in balance. Balance the proportion of inbred populations and genotype frequencies in relation allele,
Wright's law becomes (law of the Wright), it is a generalized expression of the Hardy-Weinberg law.
Inbred population frequency hybrid H and random mating populations over the desired frequency hybrid H 'ratio:
H／H’ = 2pq(1-F)/2pq=1-F
F = 1 - H/H’
The above formula shows that the average coefficient of inbreeding groups inbred population with respect to frequency over a hybrid population
reduction ratio values hybrid frequency. In fact, any group genotype frequencies deviating
Hardy-Weinberg law can be used to measure the F value, known as the fixed coefficient F (fixation index).
Inbreeding coefficient different inbred relationship between genotype groups
left over as compared with the inbred population groups,
comparing the relationship between the right is an inbred population genotype frequency different inbreeding
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Original link: https: //blog.csdn.net/zhu_si_tao/article/details/71480168