HNF4A and schizophrenia: Seeking the mechanism at the TCF gene which could account for the association between the SNP rs9960767 and schizophrenia, a recent study examined TCF4 for coding variants, and for cis-regulated variation in TCF4 gene expression correlated with the associated SNP; this study used a SNaPshot assay to detect differential allelic expression measuring the relative expression levels of mRNA containing each exonic allele [286].