Table 1.
Characteristics of South African patients with genetic neuropathies (GN), hereditary spastic paraplegia (HSP), and spastic ataxia.
| GN (n = 32) | HSP and spastic ataxia (n = 29) | Combined (n = 61) | ||||
|---|---|---|---|---|---|---|
| CMT (n = 21) | HMN (n = 7) | Other (n = 4) | HSP (n = 23) | Spastic ataxia*(n = 6) | ||
| Median AAO# (IQR) | 13 (9–19) | 17 (13–25) | 12 (2–45) | 15 (9–24) | 15 (6–25) | 15 (9–20) |
| Male sex, n (%) | 9 (43) | 5 (71) | 2 (50) | 6 (22) | 4 (67) | 26 (43) |
| Genetic ancestry | ||||||
| African n (%) | 10 (48) | 5 (71) | 1 (25) | 15 (61) | 4 (67) | 35 (57) |
| European n (%) | 11 (52) | 2 (29) | 3 (75) | 8 (35) | 1 (17) | 25 (42) |
| Indian n (%) | 0 | 0 | 0 | 0 | 1 (17) | 1 (1) |
| Solved n (%) | 11 (52) | 2 (29) | 1 (25) | 12 (52) | 2 (33) | 28 (46) |
GN, genetic neuropathies; HSP, hereditary spastic paraplegia; CMT, Charcot-Marie-Tooth disease; HMN, hereditary motor neuropathy (based on electrophysiological evidence of normal sensory nerve action potentials); AAO, age at onset (#years); IQR, interquartile range between 25th and 75th centile.
*
Refers to probands with ataxia as the predominant clinical feature. Solved refers to probands in whom a pathogenic or likely pathogenic variant was identified.