What percentage of someone’s genetic background may contribute to alcohol dependency?

The percentage of an individual genetic background that may contribute to alcohol dependency is 50%.

Explanation:

Alcohol dependency refers to a chronic disease in which the affected individual has an uncontrollable urge for alcoholic drinks. There are many factors that can cause one to depend on alcohol and one's genetic background is one of them.

Recently, researchers have been able to identify a specific gene that is responsible for development of alcoholic dependency. Before now, scientific studies have been able to proof that children born by alcoholic parents have high tendency of becoming alcoholic adults. The percentage of genetic heritage that is responsible for alcoholic use is as high as 50%

1) gene flow

- it is described as the transfer of genes from one population to another population so that frequency of gene is increased.

-a zebra migrates to join a different herd of zebras.

2) natural selection

- a mechanism of evolutionary change in which individuals with advantageous traits survive and reproduce whereas the others ( those that can not adapt) eliminate from the population.

-competition for sunlight leads to taller trees.

3) mutation

- permanent change in the nucleotide sequence of dna ( genetic material) that could have harmful or useful consequences.

-the dna of a snake changes to make its venom stronger.

4) genetic drift - it is a random phenomenon ( that occurs by chance such as fire) that results in change in the gene frequency in a small population.    

-a grassfire randomly sweeps through a population of buffalo and kills most of the animals.

explanation:

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