Meta-analyses were conducted to determine the magnitude of relationships between polymorphisms in 2 genes, ALDH2 and ADH1B, with alcohol dependence in Asians. For each gene, possession of 1 variant *2 allele was protective against alcohol dependence, and possession of a 2nd *2 allele did not offer significant additional protection. The protective effects of these 2 gene polymorphisms were independent. Diagnostic criteria, recruitment strategy, and Japanese ethnicity moderated the effect of ALDH2*2. Recruitment strategy and gender moderated the effect of ADH1B*2. These findings highlight the importance of methodological issues and potential gene-gene and gene-environment interactions that must be considered when examining relationships between genetic polymorphisms and phenotypes.

Transdermal alcohol sensors continuously collect reliable and valid data on alcohol consumption in vivo over the course of hours to weeks. Transdermal alcohol readings are highly correlated with breath alcohol measurements, but transdermal alcohol levels lag behind breath alcohol levels by one or more hours due to the longer time required for alcohol to be expelled through perspiration. By providing objective information about alcohol consumption, transdermal alcohol sensors can validate self-report and provide important information not previously available. In this article we describe the development and evaluation of currently available transdermal alcohol sensors, present the strengths and limitations of the technology, and give examples of recent research using the sensors.

Regular alcohol consumption in unfamiliar social settings has been linked to problematic drinking. A large body of indirect evidence has accumulated to suggest that alcohol's rewarding emotional effects-both negative-mood relieving and positive-mood enhancing-will be magnified when alcohol is consumed within unfamiliar versus familiar social contexts. But empirical research has never directly examined links between contextual familiarity and alcohol reward. In the current study, we mobilized novel ambulatory technology to examine the effect of social familiarity on alcohol reward in everyday drinking contexts while also examining how alcohol reward observed in these field contexts corresponds to reward observed in the laboratory. Heavy social drinking participants (N = 48, 50% male) engaged in an intensive week of ambulatory assessment. Participants wore transdermal alcohol sensors while they reported on their mood and took photographs of their social contexts in response to random prompts. Participants also attended 2 laboratory beverage-administration sessions, during which their emotional responses were assessed and transdermal sensors were calibrated to estimate breathalyzer readings (eBrACs). Results indicated a significant interaction between social familiarity and alcohol episode in everyday drinking settings, with alcohol enhancing mood to a greater extent in relatively unfamiliar versus familiar social contexts. Findings also indicated that drinking in relatively unfamiliar social settings was associated with higher eBrACs. Finally, results indicated a correspondence between some mood effects of alcohol experienced inside and outside the laboratory. This study presents a novel methodology for examining alcohol reward and indicates social familiarity as a promising direction for research seeking to explain problematic drinking. (PsycINFO Database Record

Studies of Asian college students have found that rates of binge drinking are associated with variation in the aldehyde dehydrogenase (ALDH2) gene. Chinese and Koreans have different prevalence rates of the ALDH2*2 allele, alcohol use, and alcoholism. The association of ALDH2 status and ethnic group with binge drinking was examined in 328 Chinese, Korean, and White college students. Ethnic group differences were found, with Whites having the highest rate of binge drinking, followed by Koreans and then Chinese. Among Asian participants, ALDH2 status and ethnicity related to binge drinking in an additive manner. Possessing an ALDH2*2 allele and being Chinese were protective factors, and being White and being Korean without an ALDH2*2 allele were risk factors for binge drinking. These results suggest that ALDH2 status, as well as other factors that differ in Koreans and Chinese, but do not interact with ALDH2, are associated with binge drinking among Asians.