To the Editor: We were struck by the high level of genetic loading of church attendance in adulthood (58% of variance) reported by Kenneth S. Kendler, M.D., and John Myers, M.S., in the October 2009 issue of the Journal (1). Church attendance was a factor associated with less alcohol and nicotine consumption in the study. A simple, easily defined behavior, church attendance could be interpreted as a proxy of religiosity, which is a much more complex, multidimensional construct (2). In fact, church attendance belongs to the social religiosity dimension, one of the seven religiosity dimensions derived from a factor analysis the authors performed for their questionnaire data in a previous study (2). The other six religiosity dimensions were general religiosity, involved God, forgiveness, God as a judge, unvengefulness, and thankfulness.