ATP Binding Cassette Transporter, Subfamily B ATP Binding Cassette Transporter, Subfamily B, Member 1--genetics Adolescent Adult Asian People--genetics Black People--genetics Cytochrome P-450 CYP3A--genetics Ecuador--epidemiology Ethnicity--genetics Female Gene Frequency Genotype Humans Male Middle Aged Polymerase Chain Reaction Polymorphism, Genetic--genetics Polymorphism, Restriction Fragment Length White People--genetics