Table 1.
General features of the cohort.
| Age of index patient at recruitment (years) | ||
| <10 | 9 | 4% |
| 10–25 | 42 | 18% |
| 26–50 | 104 | 45% |
| > 50 | 75 | 33% |
| Sex | ||
| Male | 110 | 48% |
| Female | 120 | 52% |
| Inheritance (based on family history) | ||
| Isolated | 110 | 48% |
| Autosomal recessive | 86 | 37% |
| Autosomal dominant | 17 | 7% |
| X-linked | 16 | 7% |
| Unknown | 1 | 1% |
| Ocular phenotype | ||
| Retinitis pigmentosa | 109 | 47% |
| Cone-rod dystrophy | 32 | 14% |
| Leber congenital amaurosis | 24 | 10% |
| Usher syndrome | 14 | 6% |
| Stargardt disease and macular dystrophy | 13 | 6% |
| Cone dystrophy | 11 | 5% |
| Chorioretinal dystrophy | 9 | 4% |
| Syndromic IRD | 9 | 4% |
| Achromatopsia | 4 | 2% |
| Congenital stationary night blindness | 2 | 1% |
| X-linked retinoschisis | 2 | 1% |
| Other | 1 | <1% |