For example, Sern-Yih Cheah and coworkers showed three potential risk factors for schizophrenia: the down-regulated 5HT2A mRNA levels in the PFC, hypermethylation of 5HT2A promoter CpG sites (cg5, cg7 and cg10) and genetic correlation with 5HT2A genotypes for rs6314 and rs6313 [147]. Here, HTR2A is linked to schizophrenia.