Indeed, accumulating evidence indicates that a common 5-HT1A gene promoter single-nucleotide polymorphism (SNP rs6295, C-1019G), which occurs in about 5–10% in Oriental populations and 40% in Caucasian population29, leads to changes in 5-HT1A receptor function that markedly affect vulnerability to psychiatric disorders, including schizophrenia30. The gene discussed is HTR1A; the disease is psychiatric disorder.