High Quality Content by WIKIPEDIA articles! In genetics, rs7997012 is a gene variation—a single nucleotide polymorphism (SNP)—in intron 2 of the human HTR2A gene that codes for the 5-HT2A receptor. The SNP varies between adenine (A) and guanine (G) DNA bases with the G-allele being most frequent. A research study found it to be related to antidepressant treatment. The research group reported that a polymorphism (rs1954787) on another gene, the GRIK4, has also shown a treatment-response-association in this kind of treatment. In a Japanese study rs7997012 was not associated with neither major depressive disorder nor bipolar disorder.