Linkage disequilibrium analysis of CYP3A4. LD is displayed by standard color schemes, with bright red for very strong LD (LOD > 2, D’ = 1), pink red (LOD > 2, D’ < 1) and blue (LOD < 2, D’ = 1) for intermediate LD, and white (LOD < 2, D’ < 1) for no LD.