The research in the lab focuses on the role of drug transporters and pharmacogenomics in the disposition of xenobiotics in the body. The first major focus utilizes both in vitro and in vivo models to evaluate genetic polymorphisms in the coding and regulatory regions of drug transporter genes that change transporter activity and expression. Genetic variability in drug transporters may alter drug disposition, including the distribution of drugs into target cells and tissues, the development of multidrug resistance, and the susceptibility to neurodegenerative diseases. The main transporters of interest include members of the ATP-binding cassette (ABC) transporter superfamily, primarily P-glycoprotein (ABCB1), MRP2 (ABCC2), and MRP3 (ABCC3), and the equilibrative and concentrative nucleoside transporters (ENTs and CNTs). These transporters are important in the disposition of many therapeutic classes of drugs, as well as other xenobiotic and endogenous substrates. A second major focus of the lab is pharmacogenomics, or the study of the relationship between a person's genotype and response to drug treatment. Native American populations are understudied in the area of pharmacogenomics; therefore, in collaboration with the Montana Cancer Institute, the lab investigates the impact of pharmacogenomics in key drug transporters and drug-metabolizing enzymes in these groups, with a particular emphasis on cancer chemotherapeutic agents.