Ethnicity-Dependent Effects of Schizophrenia Risk Variants of the OLIG2 Gene on OLIG2 Transcription and White Matter Integrity

AbstractPrevious studies have indicated associations between severalOLIG2 gene single-nucleotide polymorphisms (SNPs) and susceptibility to schizophrenia among Caucasians. Consistent with these findings, postmortem brain and diffusion tensor imaging studies have indicated that the schizophrenia-risk-associated allele (A) in theOLIG2 SNP rs1059004 predicts lowerOLIG2 gene expression in the dorsolateral prefrontal cortex (DLPFC) of schizophrenia patients and reduced white matter (WM) integrity of the corona radiata in normal brains among Caucasians. In an effort to replicate the association between this variant and WM integrity among healthy Japanese, we found that the number of A alleles was positively correlated with WM integrity in some fiber tracts, including the right posterior limb of the internal capsule, and with mean blood flow in a widespread area, including the inferior frontal operculum, orbital area, and triangular gyrus. Because the A allele affected WM integrity in opposite directions in Japanese and Caucasians, we investigated a possible association between theOLIG2 gene SNPs and the expression level ofOLIG2 transcripts in postmortem DLPFCs. We evaluated rs1059004 and additional SNPs in the 5 ′ upstream and 3′ downstream regions of rs1059004 to cover the broader region of theOLIG2 gene. The 2 SNPs (rs1059004 and rs9653711) had opposite effects onOLIG2 gene expression in the DLPFC in Japanese and Caucasians. These findings suggest ethnicity-dependent opposite...
Source: Schizophrenia Bulletin - Category: Psychiatry Source Type: research