Objective: ZNF804A is a schizophrenia risk gene that was recently identified by genome-wide association studies as well as subsequent replications. Although the results are consistent among studies in European populations, there have been conflicting reports in Chinese populations. The authors conducted both association and functional analyses to test whether ZNF804A is a risk gene for schizophrenia in Chinese populations.
Method: The authors recruited two case-control samples of independent Han Chinese (a total of 2,207 participants) from southwestern China. A total of six single-nucleotide polymorphisms (SNPs), including the key SNP (rs1344706) that showed significant association with schizophrenia in European populations and the other five promoter SNPs of ZNF804A, were tested. Based on the results of the association analysis, the authors performed two functional assays to test the impact of the risk SNP on transcriptional factor binding affinity and promoter activity.
Results: The SNP rs1344706 was not associated with schizophrenia in either of the two Han Chinese groups, and this result was confirmed by meta-analyses in five Han Chinese samples. However, the authors identified two ZNF804A promoter SNPs that were significantly associated with schizophrenia in both samples, and the significance was strengthened in the combined samples and further supported by haplotype analysis. The functional assays demonstrated that the risk SNP (rs359895) can influence Sp1 binding affinity, resulting in a higher promoter activity of the risk allele.
Conclusions: Our results suggest that ZNF804A is a common risk gene for schizophrenia in world populations and that the newly identified functional SNP (rs359895) is likely a risk SNP for schizophrenia.