The addiction-related gene content of Smokescreen is designed to be helpful in pharmacogenetic analyses of current or future addiction gene targets. In an analysis of the Psychiatric Genetic Consortium schizophrenia findings [72], 40 of the 341 protein-coding genes linked to GWAS hits were identified as targets of existing drugs or drugs undergoing Phase III trials [73]. Lencz and Malhotra conclude that six protein-coding genes (CACNA1C, CACNB2, CACNA1I, DRD2, GRIN2A, HCN1) are of greatest neuropsychiatric and genetic interest. Three of these six genes (DRD2, CACNA1I, GRIN2A) are included in Smokescreen’s group of addiction-related genes; overall, 10 of the 40 target genes are included in Smokescreen’s gene list with increased coverage, suggesting Smokescreen’s usefulness for addiction-related drug development studies. Coverage of the nicotine metabolizing enzyme genes CYP2A6 and CYP2B6, the opportunity to incorporate NMR measures in larger studies, and novel analytical methods may improve nicotine metabolism models, which currently predict between 50 and 70 % of variance in European ancestry populations [39].
