DRD2 and autism: We generated a classification matrix to determine the percent correct classification of individuals with and without autism based on DRD2 rs1800498 and PPP1R1B rs1495099 genotypes, and found that 97% of individuals from our comparison cohort and 13% of individuals with autism were correctly classified (the analysis was based on the a priori baseline frequency of 70% of individuals without autism and 30% of individuals with autism).