A recent research study on alcoholism suggests that use of illegal drugs is influenced by environmental factors but abuse and dependence are more influenced by

The answer is "it is influenced by genetic factors".

Ongoing investigations propose that basic genetic factors may make individuals defenseless against both liquor and tobacco compulsion. Obviously, both liquor and nicotine reliance keeps running in families. Identical twins are twice as likely as fraternal twins to be nicotine and liquor subordinate if the other twin is reliant. Individuals might be pretty much delicate to liquor and tobacco's belongings in view of regular hereditary varieties in the number and kind of nicotinic receptors that they have.