Even though alcohol consumption and alcohol dependence are closely related, the causes of susceptibility to the two are not necessarily the same. A study in the August issue of Alcoholism: Clinical & Experimental Research looks at the genetic and environmental causes of variation in long-term alcohol consumption, and estimates what degree of overlap may exist with causes of susceptibility to alcohol dependence. Results indicate that variation in long-term average alcohol intake is almost entirely due to genetic differences, and that some genes affect both intake and dependence while others affect only dependence.
"Alcohol consumption is about how much a person drinks at some particular time, whereas alcohol dependence is more about the effects that alcohol has, or has had, on a person their behaviour, their neurophysiology, and their relationships with other people," explained John B. Whitfield, senior scientist at the Royal Prince Alfred Hospital in Sydney and first author of the study.
"Most people consume alcohol, at least in western' societies, but only some consume it in large enough quantities which may do them harm," said Whitfield, "similarly, only some are so affected by it that they meet the psychiatric criteria for alcohol dependence.' The possible relationships between intake and dependence may be none, except during bouts of uncontrolled and extremely heavy drinking, or some overlap or common causes for each, or the same underlying causes for both. We sought to explore this relationship, which