al., 2011). Heritability of neuropsychiatric disorders like AUD is notoriously complex and has been the subject of intense investigation (for reviews, see Geschwind and Flint, 2015; McConnell et al., 2017). Studying AUD from a genetic perspective is particularly challenging due to variation in severity of disease phenotype. For example, an individual could meet either two to three of eleven diagnostic criteria in the DSM-V for a “mild” diagnosis, 4-5 for a “moderate” diagnosis, or six or more for a “severe” diagnosis (American Psychiatric Association, 2013). Such clinical heterogeneity is likely reflective of the genetic complexity underlying AUD. Identification of genes involved in AUD is crucial for understanding disease mechanisms and designing targeted treatments.
