Table 1. CAG repeat length, allele categories, age at onset and age of participants in the study.
| HD carriers | Non-carriers | Total | ||||
|---|---|---|---|---|---|---|
| Total | Symptomatic carriers | Asymptomatic carriers | ||||
| Number of subjects | 253 | 213 | 40 | 66 | 319 | |
| Expanded CAG repeat -median (range) | 44 (37-81) | 44 (39-81) a | 43 (37-48) a | - | ||
| Normal CAG repeat - median (range) | 17 (9-33) | 17 (10-33) | 17 (9-37) | 17 (10-31) | ||
| Number of alleles | Stable (CAG)£26 | 240 b | 203 b | 37 | 123 | 363 |
| Intermediate (CAG)27-35 | 12 | 9 | 3 | 9 | 21 | |
| Reduced penetrance (CAG)36-39 | 4 | 2 | 2 | - | 4 | |
| Full-penetrant (CAG)40 or more | 250 b | 212 b | 38 | - | 250 | |
| Age at disease onset (years) | - | 39 ± 12 (range 6-67) | - | - | ||
| Age (years) (mean ± SD) | - | 50.5 ± 11 (range 18-73) c | 35.85 ± 12 (range 19-77) | 40 ± 13.75 (range 19-76) | ||
a
p< 0.05, Mann-Whitney U-test;
b
one individual had a full penetrant expanded CAG repeat in both alleles;
c
p< 0.001, one-way ANOVA (Tukey)