Table 5.
Number/Percentage of Laboratories that Report Testing for Specific CYP2D6 Alleles from Proficiency Testing Data
| Allele | Tier | CAP PGx, n (%) | MG2, n (%) | |
|---|---|---|---|---|
| ∗2 | 1 | 135 (96.4) | 37 (74.0) | |
| ∗2A | 29 (20.7) | N.D. | ||
| ∗3 | 1 | 131 (93.6) | 50 (100) | |
| ∗4 | 1 | 138 (98.6) | 50 (100) | |
| ∗5 (Deletion) | 1 | 122 (87.1) | 49 (98.0) | |
| ∗6 | 1 | 134 (95.7) | 48 (96.0) | |
| ∗7 | 2 | 124 (88.6) | 26 (52.0) | |
| ∗8 | 2 | 122 (87.1) | 26 (52.0) | |
| ∗9 | 1 | 132 (94.3) | 34 (68.0) | |
| ∗10 | 1 | 134 (95.7) | 38 (76.0) | |
| ∗11 | No tier | 67 (47.9) | N.D. | |
| ∗12 | 2 | 99 (70.7) | N.D. | |
| ∗14 | 2 | 88 (62.9) | N.D. | |
| ∗15 | 2 | 60 (42.9) | N.D. | |
| ∗17 | 1 | 130 (92.9) | 28 (56.0) | |
| ∗21 | 2 | N.D. | N.D. | |
| ∗29 | 1 | 118 (84.3) | N.D. | |
| ∗31 | 2 | N.D. | N.D. | |
| ∗35 | No tier | 71 (50.7) | 16 (32.0) | |
| ∗40 | 2 | N.D. | N.D. | |
| ∗41 | 1 | 133 (95.0) | 40 (80.0) | |
| ∗42 | 2 | N.D. | N.D. | |
| ∗49 | 2 | N.D. | N.D. | |
| ∗56 | 2 | N.D. | N.D. | |
| ∗59 | 2 | N.D. | N.D. | |
| Duplication | 1 | 123 (87.9) | 47 (94.0) | |
| Hybrid alleles | ∗36 (alone or as part of ∗36+∗10) | 2 | 24 (17.1) | N.D. |
Specific CYP2D6 alleles that are queried in the College of American Pathologists (CAP) PGx and/or the German Reference Institute for Bioanalytics Molecular Genetics Group (MG)-2 proficiency testing surveys are listed, along with the tier assigned in the present article. The numbers and percentages of laboratories that reported that they test for the allele are provided. All alleles included in the CAP and/or MG2 surveys were listed, although ∗11 and ∗35 were not assigned to tier 1 or 2. Additionally, several alleles assigned to tier 2 are included in this table despite not being part of the CAP or MG2 survey (eg, ∗21, ∗31, ∗40, ∗42, ∗49, ∗56, ∗59).
N.D., no data on that allele were available from the survey.