A polymerase chain reaction-restriction fragment length polymorphism method for screening ZNF804A gene polymorphism (rs1344706) in patients with schizophrenia: a significant association.

The original ZNF804A rs1344706 risk variant was identified through genome-wide association studies as a risk factor for schizophrenia. Follow-up studies involving meta-analysis have confirmed that rs1344706 is a risk factor for schizophrenia as well as bipolar disorders. We describe here a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method to genotype ZNF804A rs1344706 variant in patients with schizophrenia. We generated a 220 bp fragment through PCR and subsequently cleaved it by the restriction endonuclease BsaBI, creating two fragments of 114 and 106 bp. Upon change in the nucleotide from T to G, the 106 bp fragment is further cleaved by BsaBI, thus creating two fragments of 87 and 19 bp. As a result, when the 220 bp fragment is cleaved by BsaBI restriction endonuclease, the TT genotype yields two fragments of 114 and 106 bp, and TG genotype four fragments of 114, 106, 87, and 19 bp, and the GG genotype three fragments of 114, 87, and 19 bp. Thus, this is a simple, fast, and cost-effective method to genotype the ZNF804A rs1344706 risk variant. Using this method, we were able to replicate an association between ZNF804A rs1344706 variant and schizophrenia in a Turkish population. Stratification analysis of the population according to the gender showed an association that was statistically significant among overall schizophrenia and male schizophrenia and the risk T allele and TT genotype of the ZNF804A gene.