Researchers at the Washington University in St. Louis (WUSTL) have found a surprising correlation between marijuana dependency and genes, as well as childhood sexual abuse. The reason why some child survivors of adversity go on to become marijuana-dependant while others are able to use the recreational drug without problems may be explained by genetic variations in the endocannabinoid system (ECS) in the brain.

A system of cannabinoid receptors located throughout the peripheral and central nervous systems of the mammalian brain comprises the ECS. It controls numerous physiological processes such as mood, sensation, memory and appetite as well as the psychoactive effects of cannabis.

Tetrahydrocannabinol (THC) is the primary psychoactive compound present in marijuana that affects numerous bodily and mental functions, owing to its close structural resemblance with endocannabinoids – the brain’s natural enzymes that control these functions. The enzymes produced in the ECS convey signals between individual cells in the...