Table 3.
Clinical characteristics of patients with different types of USH2A mutations
| M+M (n=46) | M+SNFO (n=88) | SNFO+SNFO (n=20) | Significant (P value) |
|
| Patients (RP/USH2) | 39/7 | 36/52 | 0/29 | 1:<0.001 2:<0.001 3:<0.001 |
| Onset age, yrs | 22.74±14.86 | 19.32±14.92 | 12.59±11.37 | 1:0.108 2:<0.001 3:<0.001 |
| Duration, yrs | 23.18±16.13 | 25.28±15.98 | 21.54±14.00 | 1:0.360 2:0.539 3:0.119 |
| BCVA* | 0.35±0.31 | 0.34±0.30 | 0.40±0.33 | 1:0.932 2:0.407 3:0.336 |
| Duration, ≤10 years | 0.57±0.27 | 0.50±0.32 | 0.66±0.18 | 1:0.408 2:0.329 3:0.080 |
| Duration, 10–20 years | 0.46±0.29 | 0.41±0.33 | 0.54±0.37 | 1:0.617 2:0.569 3:0.273 |
| Duration, >20 years | 0.22±0.26 | 0.26±0.25 | 0.20±0.19 | 1:0.403 2:0.670 3:0.209 |
| MD*, dB | −24.83±5.62 | −25.43±4.32 | −25.62±4.66 | 1:0.511 2:0.245 3:0.444 |
| Duration, ≤10 years | −22.32±7.05 | −22.58±6.04 | −23.96±2.99 | 1:0.387 2:0.196 3:0.343 |
| Duration, 10–20 years | −24.11±3.03 | −25.75±4.03 | −25.00±4.51 | 1:0.596 2:0.998 3:0.367 |
| Duration, >20 years | −25.60±4.68 | −26.96±2.57 | −26.63±4.72 | 1:0.331 2:0.365 3:0.480 |
| CFT*, µm | 250.43±68.66 | 229.34±67.86 | 230.38±76.44 | 1:0.098 2:0.126 3:0.585 |
| Duration, ≤10 years | 282.10±105.39 | 281.72±86.18 | 250.70±99.36 | 1:0.826 2:0.157 3:0.276 |
| Duration, 10–20 years | 256.24±52.26 | 238.22±33.58 | 232.25±22.25 | 1:0.170 2:0.456 3:0.961 |
| Duration, >20 years | 218.00±31.57 | 199.50±45.98 | 197.75±65.60 | 1:0.488 2:0.873 3:0.137 |
1:M+M versus M+SNFO; 2: M+M versus SNFO+SNFO; 3: M+SNFO versus SNFO+SNFO.
*Corrected for the time of disease duration.
M, missense; SNFO, splice-site, nonsense, frameshift, or others (readthrough, gross deletions and small indels).
RP, retinitis pigmentosa; USH2, Usher syndrome type IIa; BCVA, best Snellen corrected visual acuity; MD, mean deviation; CFT, centre foveal thickness.