Abstract
This study examined the degree to which genetic and environmental factors contribute to externalizing and internalizing problems in early adolescence, and the role of ethnic discrimination in moderating genetic and environmental influences. The sample included 740 racially/ethnically minoritized adolescent twins (50.3% female, mean age = 11.04 years) from the Adolescent Brain Cognitive Development (ABCD) Study. Adolescents reported on their ethnic discrimination experiences, and parents reported on adolescents' externalizing and internalizing problems. Using univariate biometric twin modeling, we found that both genetic and environmental factors contributed to individual differences in externalizing and internalizing problems. Ethnic discrimination experiences moderated genetic influences on externalizing and internalizing problems, such that genetic influences were higher among youth who experienced higher levels of ethnic discrimination. Ethnic discrimination experiences exacerbate genetic influences on externalizing and internalizing problems among racial/ethnic minoritized adolescents. These findings advance our understanding of the interplay between genetic and cultural factors underlying externalizing and internalizing psychopathology among racially/ethnically minoritized adolescents.