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)39/736/520/291:<0.001
2:<0.001
3:<0.001
Onset age, yrs22.74±14.8619.32±14.9212.59±11.371:0.108
2:<0.001
3:<0.001
Duration, yrs23.18±16.1325.28±15.9821.54±14.001:0.360
2:0.539
3:0.119
BCVA*0.35±0.310.34±0.300.40±0.331:0.932
2:0.407
3:0.336
Duration, ≤10 years0.57±0.270.50±0.320.66±0.181:0.408
2:0.329
3:0.080
Duration, 10–20 years0.46±0.290.41±0.330.54±0.371:0.617
2:0.569
3:0.273
Duration, >20 years0.22±0.260.26±0.250.20±0.191:0.403
2:0.670
3:0.209
MD*, dB−24.83±5.62−25.43±4.32−25.62±4.661:0.511
2:0.245
3:0.444
Duration, ≤10 years−22.32±7.05−22.58±6.04−23.96±2.991:0.387
2:0.196
3:0.343
Duration, 10–20 years−24.11±3.03−25.75±4.03−25.00±4.511:0.596
2:0.998
3:0.367
Duration, >20 years−25.60±4.68−26.96±2.57−26.63±4.721:0.331
2:0.365
3:0.480
CFT*, µm250.43±68.66229.34±67.86230.38±76.441:0.098
2:0.126
3:0.585
Duration, ≤10 years282.10±105.39281.72±86.18250.70±99.361:0.826
2:0.157
3:0.276
Duration, 10–20 years256.24±52.26238.22±33.58232.25±22.251:0.170
2:0.456
3:0.961
Duration, >20 years218.00±31.57199.50±45.98197.75±65.601:0.488
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.