With the comprehensive and multimodal longitudinal data available in COGA, we can characterize the pathways by which genetic and environmental influences on alcohol‐related problems unfold. Consistent with earlier studies in the literature, 48 , 49 we found that genetic risk for alcohol problems manifests in adolescence and early adulthood as a constellation of clinical behaviors related to impulsivity and behavioral undercontrol, often called the externalizing spectrum. 21 , 50 , 51 , 52 , 53 , 54 These childhood behavior problems 42 and traits related to impulsivity, such as sensation‐seeking, reflect early manifestations of genetic risk for alcohol and other substance use problems. 55 , 56 , 57 With the greater availability of alcohol as individuals age from later adolescence to emerging adulthood, these same genetic influences begin to impact patterns of alcohol use, 58 the rate of escalation in hazardous use, 59 and the development of problems. 42 Measures of the intensity of response to alcohol are additional early indicators of genetic risk for alcohol problems, and include both a low level of response seen at peak and falling
