Identification of a naturally occurring Pro₁₅-Ser₁₅ substitution in the serotonin(5A) receptor gene in alcoholics and healthy volunteers

We screened the serotonin(5A) receptor gene coding region in 186 unrelated alcoholic patients and 187 controls. A relatively abundant amino acid substitution and two synonymous DNA substitutions were detected. Two synonymous variants, A12T and C789T, had rarer-allele frequencies of 23% and 1%, respectively. The Pro15Ser substitution is located in the amino terminal, extracellular domain of the receptor adjacent to a putative phosphorylation site. Pro15Ser had rarer-allele frequencies of 8.1% and 5.9% in Finnish alcoholic patients and controls, respectively (p = n.s.).