Lack of association of serotonin-2A receptor gene polymorphism (T102C) with suicidal ideation and suicide.

Serotonergic dysfunction has been implicated in the pathophysiology of affective disorders and suicidality. Especially the density of the 5-HT2A receptor was claimed as being increased in suicidality, proposed as an adaptive upregulation due to reduced serotonergic transmission. Recent studies have shown an association of allele C of the 5-HT2A-T102C polymorphism with suicidal ideation in patients with major depression. The purpose of this study was to test whether this proposed marker indicates susceptibility not only to suicidal ideation in depressed patients but also to suicidality as a syndrome. We investigated the 5-HT2A-T102C polymorphism in 131 suicide victims with unknown underlying psychiatric diagnoses, 84 patients with major depression with or without suicidal ideation, and 125 healthy controls. We were unable to find any association of genotype or allele frequencies to major depression, suicidal ideation, or suicide as a syndrome. Thus, our results suggest that this polymorphism may not commonly be involved in the susceptibility to suicidality. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 96:831-835, 2000.