TABLE 2.
Phenotype of variants causing X‐linked Charcot‐Marie‐Tooth disease, stratified by type of mutation.
| Missense | Nonsense | Frameshift | 5'UTR | |
|---|---|---|---|---|
| Patients, % (n) | 84 (230) | 10 (27) | 3 (9) | 3 (8) |
| Families, % (n) | 83 (134) | 9 (15) | 4% (7) | 3 (5) |
| Variants, % (n) | 84 (73) | 3 (2) | 7 (6) | 6 (5) |
| Male/Female | 106/124 | 14/13 | 3/6 | 5/3 |
| Age at evaluation, years | 46 | 48 | 43 | 38 |
| CMTES, mean | 9 | 11 | 10 | 7 |
| ONLS, mean | 2.8 | 3.5 | 2.9 | 2.3 |
| Age of onset, mean years | 19 | 15 | 15 | 20 |
| MNVC median nerve, mean m/s | 39 | 39 | 38 | 42 |
| MNCV ulnar nerve, mean m/s | 43 | 45 | 35 | 47 |
| Sum of the CMAP of the median and ulnar nerves, mV | 10.8 | 9.4 | 7 | 11 |
Abbreviations: 5′UTR, 5′ untranslated region; CMAP, compound muscle action potential; CMTES, Charcot‐Marie‐Tooth Examination Score version 2; MNCV, motor nerve conduction velocity; ONLS, Overall Neuropathy Limitation Score; SD, standard deviation.