Advisory Committee Chair
Advisory Committee Members
Date of Award
Degree Name by School
Master of Science (MS) College of Arts and Sciences
Substance use, including the use of tobacco, alcohol, marijuana, and other drugs, is most likely to begin during adolescence or emerging adulthood. Substance use during these developmental periods has been linked with a number of negative physical, mental, and cognitive health outcomes. Some of these long-term negative effects of substance use during adolescence and emerging adulthood may be explained by epigenetic changes through a process called DNA methylation. However, much of the research on substance use and DNA methylation has focused on prenatal drug exposure and its relationship to differential methylation profiles during childhood and young adulthood. By contrast, little is known about the epigenetic impact of substance use during adolescence. The present study examined the associations between DNA methylation and alcohol, tobacco, and marijuana use during early adolescence and young adulthood. The analyses focused on three genes, AHRR, NR2B, and COMT, because their methylation has been implicated with substance use. Participants included 290 young adults from the Birmingham Youth Violence Study who also provided data in early adolescence (Mage = 13.1), late adolescence (Mage = 17.6), and young adulthood (Mage = 27.4). Analyses included 60% females, 82% minorities primarily consisting of African Americans, and 18% European Americans. Substance use was self-reported at each developmental period. DNA methylation beta values were measured with salivary DNA in young adulthood and averaged for each gene. The relationships between alcohol, tobacco, and marijuana use iv and DNA methylation were tested using multivariate regressions, adjusting for sex, ethnicity, smoking history during late adolescence and early adulthood, and age in young adulthood. The delta R2 values when the alcohol, tobacco, or marijuana use were added in the model ranged from 0.00 to 0.02, all p > 0.05. Moreover, in the combined substance use models, the combination of tobacco, alcohol, and marijuana use did not significantly affect R2 in any model (p < 0.05).
McMahan, Kristina Brooke, "Adolescent Alcohol, tobacco, and Marijuana Use and DMA Methylation in Young Adulthood" (2022). All ETDs from UAB. 133.