has been observed in children of individuals with alcohol use disorder, even when these
children were given up for adoption at birth and raised by adoptive parents who did not
have the disorder.
Recent advances in our understanding of  genes that operate through intermediate
characteristics (or phe notypes) to affect the risk of alco hol use disorder can help to identify
individuals who might be at pa rticularly low or high risk for alcohol use disorder. Among
the low-risk phenotypes are the acute alcohol-related skin flush (seen most prominently in
Asians). High vulnerability is associated with  preexisting schizophrenia or bipolar disor-
der, as well as impulsivity (producing enha nced rates of all substance use disorders and
gambling disorder), and a high risk specifically for alcohol use disorder is associated with
a low level of response (low sensitivity) to alcohol. A number of gene variations may ac-
count for low response to alcohol or modulate the dopamine reward systems; it is impor-
tant to note, however, that any one gene variat ion is likely to explain only 1%–2% of the risk
for these disorders.
Course modifiers. In general, high levels of impulsivity are associated with an earlier
onset and more severe alcohol use disorder. 
Culture-Related Diagnostic Issues
In most cultures, alcohol is the most frequently used intoxicating substance and contrib-
utes to considerable morbidity and mortality. An estimate d 3.8% of all global deaths and
4.6% of global disability-adjusted life-years are attribut able to alcohol. In the United States,
80% of adults (age 18 years and older) have co nsumed alcohol at some  time in their lives,
and 65% are current drinkers (last 12 months).  An estimated 3.6% of the world population