The association between CYP2C19 activity score and the probability of low symptom severity did not change when including schizophrenia-PRS (OR = 1.59, 95% CI = 1.13–2.24, p = 8.51x10−3, Supplementary Table 14), schizophrenia-PRS and the first 10 PCs (OR = 1.63, 95% CI = 1.97–2.43, p = 0.02, Supplementary Table 15), or the top two GWAS hits (NFIB rs1923778, PTPRD rs4742565) (OR = 1.60, 95% CI = 1.06–2.42, p = 0.02, Supplementary Table 16). This evidence concerns the gene NFIB and schizophrenia.