A priori SNP analyses revealed a significant association between the combined impulsivity phenotype and two SNPs within the 5-HT2a receptor gene (HTR2A; rs6313 and rs6311).
The complementary makers (rs594242-rs6311: G-C and rs6311: C) were associated with increased risk for non-violent (p=0.01; p=0.009 respectively) and impulsive suicidal behavior (p=0.03; p=0.01 respectively).