rs3131296

A candidate gene association study of HLA-DRB1 tagging SNPs in schizophrenia among 332 British cases (219 male, 113 female; mean age 32-36 years) and 155 controls (mean age 40-42 years) recruited through family-based (132 trios, 92 duos) and case-control designs. The DRB1*1303 allele showed marginal protective association (OR=0.42, 95% CI 0.27-0.66, χ²=4.138, P=0.042), and rs424232 showed significant protective association with schizophrenia (OR=0.69, 95% CI 0.54-0.88, χ²=9.404, P=0.002). The authors failed to confirm association of candidate DRB1 risk alleles but noted the association signal may extend beyond the HLA locus toward the NOTCH4 gene.

A case-control study of 2,019 schizophrenia patients and 2,579 Japanese controls found the rs12807809-rs12278912 haplotype in the NRGN gene (chromosome 11q24.2) significantly associated with schizophrenia (global P = 0.0042). The TG haplotype was associated with increased risk (OR = 1.14, P = 0.0019), while the TA haplotype was protective (OR = 0.85, P = 0.0053). Gene expression analysis demonstrated the high-risk TG haplotype had significantly lower NRGN expression than the protective TA haplotype (P = 0.007 in HapMap samples, P = 0.002 in combined case-control samples).

This comprehensive review examines the genomics of schizophrenia and pharmacogenomics of antipsychotic drugs, synthesizing evidence on over 200 genes associated with psychotic disorders. The authors discuss five categories of genes relevant to antipsychotic response: disease-associated genes, mechanism-of-action genes, drug metabolism genes (particularly CYP2D6, CYP2C19, CYP2C9, CYP3A4), drug transporter genes, and pleiotropic genes. The review details pharmacogenomic profiles of 20+ antipsychotic drugs and demonstrates significant ethnic and interindividual variation in drug metabolism phenotypes, with examples including CYP2D6 extensive metabolizers (55.71% of population), intermediate metabolizers (34.7%), poor metabolizers (2.28%), and ultra-rapid metabolizers (7.31%).

This review comprehensively summarizes the latest genetic studies on schizophrenia, including family studies (heritability ~80%), genome-wide association studies, epigenetic mechanisms, candidate gene investigations, and next-generation sequencing findings. Key GWAS findings identified 108 schizophrenia-associated loci including variants in MIR137 (rs1625579), TCF4 (rs12966547), CSMD1 (rs10503253), CACNA1C (rs4765905), ANK3 (rs10761482), and MHC region variants, with evidence for polygenetic inheritance involving both common SNPs and rare copy number variations.

This systematic review of 98 studies examined biological predictors of clozapine response in treatment-resistant schizophrenia patients. Of 379 different gene variants investigated across 70 genetic studies, only three variants (DRD3 Ser9Gly rs6280, HTR2A His452Tyr, and GNB3 C825T) achieved independent replication. Non-genetic predictors included higher prefrontal cortical volumes and lower HVA:5-HIAA ratio in cerebrospinal fluid.

A systematic review of 98 studies investigating biological predictors of clozapine response in treatment-resistant schizophrenia. Of 70 genetic studies examining 379 variants, only three genetic variants have independently replicated findings: DRD3 Ser9Gly (rs6280), HTR2A His452Tyr, and GNB3 C825T (rs5442/rs5443). Non-genetic predictors include higher prefrontal cortical structural integrity and activity, and lower HVA:5-HIAA ratio in cerebrospinal fluid.