Although some investigators have identified genetic components of susceptibility to cocaine dependence, only a small portion of the heritability is explained by those findings [17]. So many of the genetic susceptibility makers or genetic mechanisms for crack/cocaine dependence are still unknown. The identification of these new genetic markers will contribute to prevent and to treat drug abuse/dependent patients. In the present study, we evaluated three SNPs in BCHE, all of which are potentially involved in cocaine metabolism. Although we did not find an association between those markers and cocaine dependence per se, we observed an association between the known functional genotype (the K variant) and a preference for the inhalation (crack smoking) route of cocaine administration. Further studies involving a replication in other independent case-control samples and/or investigation involving a correlation between the function and the genetic variants and/or sequencing of this region would be very welcome to clarify the preliminary findings of the present report.
