A pharmacogenetic study of risperidone on chemokine (C–C motif) ligand 2 (CCL2) in Chinese Han schizophrenia patients

• We recruit two cohorts of Chinese schizophrenic patients from two geographic areas.
• We detect significant effect of CCL2 polymorphisms with risperidone response.
• Population stratification may have influenced the results.

Previous observations of the pathophysiological distribution and pharmacological profile of the chemokine (C–C motif) ligand 2 (CCL2) have indicated its potential role in antipsychotic drug actions. More information on the pharmacogenetics of CCL2 may therefore be useful in developing individualized therapy. However, to our knowledge, rare studies have been reported in this area. This investigation was attempted to clarify whether CCL2 polymorphism could affect risperidone efficacy. We genotyped four SNPs (rs4795893, rs1024611, rs4586 and rs2857657) distributed throughout the CCL2 gene and examined them for association using the Positive and Negative Syndrome Scale (PANSS) score in two independent cohorts of Chinese schizophrenic patients (n = 208) from two different geographic areas, following an 8-week period of risperidone monotherapy. We found that all genotyped SNPs were significantly associated with risperidone treatment (rs4795893: p = 1.66E− 04, rs4586: p = 0.001, rs2857657: p = 0.004, at week 4, in ANOVA). Our results indicate that there may be some effect of variations in the CCL2 gene on therapeutic efficacy of risperidone, and the associated polymorphisms may be a potential genetic marker for predicting the therapeutic effect of risperidone.