. . . . . . . . . . . . "[Dopamine D4 receptor (DRD4) and serotonin transporter (SERT) gene polymorphisms were studied, as possible genetic risk factors for substance dependence.]. Sentence from MEDLINE/PubMed, a database of the U.S. National Library of Medicine."@en . . . . . "2015-02-27"^^ . . "Gene-disease associations inferred from text-mining the literature."@en . "DisGeNET evidence - LITERATURE"@en . "2015-08-25T14:44:41+02:00"^^ . . . . . . . . . . . "v3.0.0.0" . "v3.0.0" .