The present study is among the first to examine the extent to which genetic and environmental factors contribute to religious service attendance and alcohol involvement in Blacks. Two findings are noteworthy. First, unlike in the White twins, shared environment contributed minimally to individual differences in C-RA, A-RA, ever drinking, timing of first alcohol use, and AUD in Blacks. This supports the idea that adult indices of religious service attendance might reflect the more heritable aspects of religiosity, such as personal devotion,5,20 and might relate to alcohol use via shared inherited attributes, such as personality. Second, only A-RA was associated with alcohol involvement in Blacks. Similar to the White twins, the relationship with AUD was due to genetic factors, but the relationship between A-RA and ever drinking was entirely due to individual-specific factors (in contrast to shared and individual-specific environmental factors in White twins). Unlike the negative correlations between C-RA and ever drinking, which likely reflect the role of religious involvement as a deterrent to drinking onset, the correlation between A-RA and ever drinking might be indicative of the higher prevalence
