. . . . . . . . . . . . "[Nicotine-induced antinociception, rewarding effects, and physical dependence are decreased in mice lacking the preproenkephalin gene.]. Sentence from MEDLINE/PubMed, a database of the U.S. National Library of Medicine."@en . . . . . "2013-07-24"^^ . . "Gene-disease associations manually curated."@en . "DisGeNET evidence - CURATED"@en . "2014-10-02T12:32:11+02:00"^^ . . . . . . . . . . . "v2.1.0.0" . "v2.1.0" .