Referral source, age, and outcome of presymptomatic tests (n=78)
| Referral source and age (y) | Normal | Abnormal | Total |
| Clinical Geneticists | |||
| 0–15 | — | — | — |
| 16–20 | 8 | — | 8 |
| 21–30 | 18 | 2 | 20 |
| 31–40 | 12 | 6 | 18 |
| 41–50 | 9 | 2 | 11 |
| 51–60 | 6 | 1 | 7 |
| 61–70 | 1 | 3 | 4 |
| 71–80 | 2 | 1 | 3 |
| >80 | — | 1 | 1 |
| Paediatricians | |||
| 31–40 | 3 | — | 3 |
| Neurologists | |||
| 17–20 | 1 | — | 1 |
| 31–40 | 1 | — | 1 |
| Others | |||
| 31–40 | 1 | — | 1 |
| Total | 62 | 16 | 78 |