FAT3 and heroin dependence: Because determining associations between functional polymorphisms and heroin addiction would be meaningful, we used HapMap (Han Chinese population) HCB data to systematically scan the promoter, 5’UTR, 3’UTR, exon, and intron-exon border regions of FAT3, KTN1, DLG2 and DCC, and 20 SNPs were selected to do association analysis with heroin addiction.