Table 1: Frequency of alleles and diplotypes among patients tested in primary care whose DNA was fully genotyped.
| Gene | Allele/diplotype | No. (%) of patients (n = 185) | 95% confidence interval | Phenotype |
|---|---|---|---|---|
|
SLCO1B1 rs4149056 |
T/T | 132 (71) | 64-77 | Normal function |
| T/C | 49 (26) | 21-33 | Intermediate function | |
| C/C | 4 (2) | 0-4 | Low activity | |
|
G6PD rs5030868 |
C/C | 185 (100) | 98-100 | Normal variant |
| C/T | 0 (0) | 0-2 | Variable activity | |
| T/T | 0 (0) | 0-2 | Low activity | |
|
VKORC1 rs9923231 |
G/G | 38 (20) | 15-27 | Normal activity |
| G/A | 89 (48) | 41-55 | Intermediate activity | |
| A/A | 58 (31) | 25-38 | Low activity | |
| HLA-B*58:01 | *58:01 negative | 176 (95) | 91-97 | Normal |
| *58:01 positive | 7 (4) | 2-8 | Increased hypersensitivity | |
| Undetermined | 2 (1) | 0-4 | Unknown | |
| CYP2C19 | *1/*1 | 80 (43) | 36-50 | Extensive metabolizer |
| *1/*2,*2/*17,*1/*4,*1/*8 | 55 (30) | 24-37 | Intermediate metabolizer | |
| *2/*2,*2/*3,*3/*3 | 8 (4) | 2-8 | Poor metabolizer | |
| *1/*17,*17/*17 | 42 (23) | 17-29 | Ultrarapid metabolizer | |
| CYP2C9 | *1/*1, | 118 (64) | 57-70 | Extensive metabolizer |
| *1/*2,*1/*3,*2/*2,*2/*3 | 62 (34) | 27-41 | Intermediate metabolizer | |
| *3/*3 | 5 (3) | 1-6 | Poor metabolizer | |
|
CYP2D6 Codeine CPIC guidelines† |
*1/*1,*1,*2,*2/*2,*1/*10,(*10/*10)3N,(*2/*4)3N,*1/*17,*1/*3,*1/*4,*1/*5,*1/*41,*2/*10,*2/*4,*2/*5,*2/*9,*2/*41,*10/*10,*41/*41 | 148 (80) | 74-85 | Extensive metabolizer |
| *3/*41,*3/*9,*4/*10,*4/*9,*4/*41,*5/*10,*5/*9 | 19 (10) | 7-15 | Intermediate metabolizer | |
| *3/*4,*4/*14A,*4/*4,*4/*5,*4/*6 | 13 (7) | 4-12 | Poor metabolizer | |
| (*1/*1)xN,(*1/*10)3N,(*1/*2)3N,(*2/*2)3N | 5 (3) | 1-6 | Ultrarapid metabolizer | |
|
CYP2D6 DPWG guidelines† |
*1/*1,*1,*2,*1/*10,*1/*17,*1/*41,*2/*2,*2/*10,*2/*41,*2/*9,(*1/*10)3N | 94 (51) | 44-58 | Extensive metabolizer |
| (*2/*4)3N,*1/*3,*1/*4,*1/*5,*2/*4,*2/*3,*10/*10,(*10/*10)3N, *2/*5,*41/*41,*3/*41,*3/*9,*4/*9,*4/*10,*4/*41,*5/*10,*5/*9 | 74 (40) | 33-47 | Intermediate metabolizer | |
| *3/*4,*4/*14A,*4/*4,*4/*5,*4/*6 | 13 (7) | 4-12 | Poor metabolizer | |
| (*1/*1)xN,(*1/*2)3N,(*2/*2)3N | 4 (2) | 1-5 | Ultrarapid metabolizer |
Note: CPIC = Clinical Pharmacogenetics Implementation Consortium, DPWG = Dutch Pharmacogenetics Working Group.
†Ambiguous genotypes DPWG CYP2D6 (*2/*4)3N and CPIC CYP2D6 (*1/*10)3N were assigned the "worst-case" phenotype.