A cross-generational comparison of alcohol challenges at about age 20 in 40 father-offspring pairs

A low level of response (LR) to alcohol is one of several genetically-influenced phenotypes associated with an elevated risk for heavy drinking and alcoholism. While most studies support the influence of genes for this characteristic, no data to date have addressed how LR established from alcohol challenges performs in similarly aged subjects across generations.

Between 1978 and 1988, 18-to-25-year-old non-alcohol-dependent Caucasian male drinkers participated in the San Diego Prospective Study alcohol challenges. The paradigms included self-reports of feelings of "High" and "Intoxication," as well as alcohol-related changes in body sway. In recent years, 40 18-to-29-year-old offspring of 25 of these original probands were tested using a similar protocol.

Despite the passage of two decades between laboratory sessions across generations, for family history positive (FHP) subjects, significant positive correlations were observed for subjective feelings of intoxication and body sway after alcohol. Parent-offspring correlations were in the predicted direction for subjective feelings for family history negatives (FHNs), but were not significant. Across offspring, LR values were lower for FHPs overall, with significant differences at 60 or 90 min for five items.

The similarities in LR across generations, while not proving heritability, are consistent with prior reports regarding genetic influences in the LR to alcohol. The significant correlations across generations and over two decades support the reliability of the alcohol challenge results.