What are the factors affecting the Hardy-Weinberg equilibrium?
Factors affecting the Hardy-Weinberg equilibrium are:
1)Mutations:
- These are sudden, large, and inheritable changes in the genetic material can occur in all directions.
-Sometimes the mutations are preadaptive and appear even without exposure to a specific environment. These can express and become advantageous only when if it gets exposure to a new environment, the hatch only selects the preadaptive mutations that occurred earlier.
2)Recombinations during Sexual Reproduction:
Recombination during sexual reproduction involves the reshuffling of genes of chromosomes. Chances of recombination are more in those organisms which undergo sexual reproduction which involves gametogenesis followed by fertilization.
-Recombination also occurs during an independent assortment of chromosomes that is during the arrangement of bivalents during metaphase I of meiosis.
3)Genetic Drift:
-It always influences frequencies of alleles and is inversely proportional to the size of the population. So genetic drift is most important in very small populations in which there are increased chances of inbreeding which increases the frequency of individuals homozygous for recessive alleles, many of which may be deleterious.
-Genetic drift occurs when a small group separates from a larger population and may not have all the alleles or may differ from the parental population in the frequencies of certain genes.
- In a small population, a chance event, for example, a snowstorm may increase the frequency of a character having little adaptive value.
4)Gene migration:
In population genetics, the gene flow is also known as gene migration or allele flow. This is the transfer of genetic variation from one population to another. The two populations are considered to have equivalent allele frequencies and can effectively be a single population if the rate of gene flow is high.
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