Fig. 1.

CYP3A4 and CYP3A5 polymorphisms population frequencies. CYP3A4 and CYP3A5 are located in tandem on chromosome 7q21. Two CYP3A4 and one CYP3A5 SNP were selected: (1) CYP3A4 T16090C, a T to C polymorphism within intron-7, 16,090 base pairs from the CYP3A4 cap site (rs2246709); (2) CYP3A4 A–392G, an A to G polymorphism, and also the most common variant of CYP3A4, located in the 5′-flanking region (rs2740574), and (3) CYP3A5 A6986G, an A to G polymorphism located in intron-3, responsible for alternative splicing and protein truncation (rs776746). The extent of linkage disequilibrium between loci is represented as R-squared (R²). Allele frequencies in Caucasian and African-Americans made available dbSNP (http://www.ncbi.nlm.nih.gov/SNP) or the Pharmacogenomics Knowledge Base (http://www.pharmgkb.org) and in the AASK population are also shown.