Same Genes at Play in Marijuana Use, Alcohol Dependence

The environmental factors that contribute to marijuana use and alcohol dependence differ significantly, but similar genes are involved in influencing people to drink and use marijuana, according to researchers.

WebMD reported Dec. 18 that a study of identical and fraternal twins ages 24-36 concluded that more than half of the variance in alcohol and marijuana use and dependence could be traced to genetic factors.

“We found considerable overlap between the genes that contribute to marijuana dependencies and alcohol use and dependence,” said researcher Carolyn Sartor, Ph.D.

The study appears in the online edition of the journal Alcoholism: Clinical & Experimental Research.