A series of functional studies substantiated the above disease-SERINC2 associations, which included (i) the significant expression of SERINC2 mRNA in brain regions, (ii) differential expression of SERINC2 mRNA in the brains of individuals with alcoholism and schizophrenia compared to controls, and (iii) the regulation of SERINC2 mRNA expression in the brain, intracranial volume (ICV), subcortical grey matter volumes (GMVs), and cortical surface area (SA) and thickness (TH) by disease-risk alleles. The gene discussed is SERINC2; the disease is alcohol drinking.