Genetic Variability in CYP2D6 in U.S Active Duty Population

Inclusion criteria: * Active duty Service member, (male or female) 18 to 60 years of age (inclusive) at the time of enrollment * Written informed consent for phase 1 must be obtained * Written informed consent for phase 2 must be obtained from the subject before the screening procedures * Free of significant health problems as established by medical history, laboratory and clinical examination before entering the study * If the subject is female, she must be of non-childbearing potential (either surgically sterilized or one year post-menopausal) or, if of childbearing potential, she must be capable of preventing pregnancy, have a negative pregnancy test at the time of the administration of primaquine , and must agree to continue such precautions until 48 hours after primaquine administration. * Normal (non-deficient) G6PD (glucose-6-phosphate dehydrogenase) phenotype (range: 4.6 to 13.5 units/gm hemoglobin) * Subjects must obtain approval from his or her supervisor per Walter Reed Army Institute of Research (WRAIR) Policy 06-15 in order to be participate in the PQ PK portion of phase 2 Exclusion criteria: * Use of any investigational or non-registered drug within 30 days preceding the primaquine dosing. * Pregnant (positive urine β-HCG) or nursing at screening or plans to become pregnant or nurse from the time of enrollment until 48 hours after primaquine dosing. * Allergy to primaquine * Use of medications known to cause drug interactions with primaquine or CYP2D6 * Acute or chronic, clinically significant, pulmonary, cardiovascular, hepatic, neurologic, or renal functional abnormality, as determined by history, physical examination, and laboratory evaluation * History of hemolytic anemia * Any abnormal baseline laboratory screening tests listed below (normal values are defined by the current Quest Diagnostics reference guide on file in the CTC): * ALT (alanine aminotransferase)above normal range * Glomerular filtration rate (GFR) below normal range for the subject's ethnicity * Hemoglobin below normal range * Hepatomegaly, right upper quadrant abdominal pain or tenderness * Suspected or known current alcohol abuse as determined from the medical history or by physical examination * Use of any drugs that may cause hemolytic anemia and/or bone marrow suppression such as quinacrine, dapsone, rifampin, colchicine, ribavirin, penicillamine and sulfonamides. * Any other significant finding that in the opinion of the investigator would increase the risk of having an adverse outcome from participating in this study