Table 3.
Incidence of inhibitors by genetic mutation
| Risk level | Sub‐mutation | N | Developed inhibitor |
|---|---|---|---|
| n (%) | |||
| High‐risk | Intron 22a | 24 | 15 (62.5) |
| Small deletionb | 7 | 4 (57.1) | |
| Nonsense mutations | 5 | 1 (20.0) | |
| Intron 1 | 3 | 3 (100.0) | |
| Large deletion | 2 | 1 (50.0) | |
| Missense mutationsa | 1 | 0 (0.0) | |
| Low‐risk | Missense mutations | 6 | 0 (0.0) |
| Duplication | 2 | 0 (0.0) | |
| Splice site mutation | 2 | 0 (0.0) | |
| Large duplication | 1 | 1 (100.0) | |
| Large insertion | 1 | 0 (0.0) | |
| Small deletionb | 1 | 0 (0.0) | |
| Small duplication | 1 | 0 (0.0) | |
| Small insertionb | 1 | 0 (0.0) | |
| Missing | Missing | 2 | 1 (50.0) |
Abbreviations: N, number of mutations; n, number of patients with a given mutation who developed an inhibitor.
a
One patient had two mutations (intron 22 and missense mutation); as the patient had both a high‐ and low‐risk mutation, both mutations for this patient are listed under high risk.
b
Small deletion and insertion outside location 1213 or 1460 were considered high risk.