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OBJECTIVE Clinical response to antipsychotic medications can vary markedly in patients with schizophrenia. Identifying genetic variants associated with treatment response could help optimize patient care and outcome. To this end, we carried out a large-scale candidate gene study to identify genetic risk factors predictive of paliperidone efficacy. PATIENTS AND METHODS A central nervous system custom chip containing single nucleotide polymorphisms from 1204 candidate genes was utilized to genotype a discovery cohort of 684 schizophrenia patients from four clinical studies of paliperidone extended-release and paliperidone palmitate. Variants predictive of paliperidone efficacy were identified and further tested in four independent replication cohorts of schizophrenic patients (N=2856). RESULTS We identified an SNP in ERBB4 that may contribute toward differential treatment response to paliperidone. The association trended in the same direction as the discovery cohort in two of the four replication cohorts, but ultimately did not survive multiple testing corrections. The association was not replicated in the other two independent cohorts. We also report several SNPs in well-known schizophrenia candidate genes that show suggestive associations with paliperidone efficacy. CONCLUSION These preliminary findings suggest that genetic variation in the ERBB4 gene may differentially affect treatment response to paliperidone in individuals with schizophrenia. They implicate the neuregulin 1 (NRG1)-ErbB4 pathway for modulating antipsychotic response. However, these findings were not robustly reproduced in replication cohorts.

To develop a predictive genetic signature for the development of bortezomib-induced peripheral neuropathy (PN).Two thousand and sixteen single-nucleotide polymorphisms (SNPs) were genotyped in 139 samples from myeloma patients treated with bortezomib-melphalan-prednisone in the VISTA phase 3 trial. Single-marker association analysis for PN onset and time/cumulative dose to PN onset using the Cox proportional hazards model and multiple covariates was performed under additive, dominant, and recessive genotypic models, followed by correction for multiplicity. Associations were also pursued in a cohort of 212 samples from patients treated with bortezomib-dexamethasone in the IFM 2005-01 phase 3 trial.In the VISTA cohort, after Bonferroni correction, two SNPs significantly associated with time to onset of PN [CTLA4 rs4553808, false discovery rate (FDR)=0.002] and time to onset of grade of at least 2 PN (PSMB1 rs1474642, FDR=0.014). Using FDR less than 0.05 as the threshold, two additional SNPs significantly associated with time to onset of grade of at least 2 (CTSS rs12568757, FDR=0.027) or grade of at least 3 PN (GJE1 rs11974610, FDR=0.041). DYNC1I1 rs916758 significantly associated (FDR=0.012) with cumulative dose to onset of grade of at least 2 PN. These associations were generally not detected in the IFM 2005-01 cohort, although CTLA4 rs4553808 showed the same trend in association with time to onset (P=0.138). In addition, in the IFM 2005-01 cohort, TCF4 rs1261134 significantly associated with onset of any neurologic event (FDR=0.048).Genes associated with immune function (CTLA4, CTSS), reflexive coupling within Schwann cells (GJE1), drug binding (PSMB1), and neuron function (TCF4, DYNC1I1) associated with bortezomib-induced PN in this study.