Table 3. Summary of phenotypes associated with the previously reported USH2A variants that were identified in the present series.
| Change in USH2A | Number of previously reported cases | References | |||||
|---|---|---|---|---|---|---|---|
| Nonsyndromic retinitis pigmentosa | Usher type II | Atypical Usher | Usher. type I | Usher type III | Asymptomatic | ||
| c.2276G>T, p.(Cys759Phe) | 96 (12 hom) | 14 | 5 | 1a | — | 1 (hom) | 8,15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26 |
| c.2299delG, p.(Glu767Serfs*21) | 58 | 327 (46 hom) | 6 (3 hom) | — | 1 | — | 8, 9, 10, 11, 15, 16, 17, 19, 20, 21, 22, 24, 25, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43 |
| c.2332G>T p.(Asp778Tyr) | — | 1 | — | — | — | — | 35 |
| c.2802 T>G, p.(Cys934Trp) | 1 | — | — | — | — | — | 44 |
| c.3902G>T, p.(Gly1301Val) | — | — | — | 1* | — | — | 40 |
| c.5776+1G>A | — | 4 | — | — | 1 | — | 21, 24, 25, 40 |
| 7595-3C>G, p.Pro2533Asnfs*5 | — | 5 | — | — | — | — | 8, 20, 45 |
| c.9371+1G>C | — | 1 | — | — | — | — | 8 |
| c.10073 G>A, p.(Cys3358Tyr) | 5 | — | 1 | — | — | — | 5, 8, 23, 26, 41 |
| c.11156 G>A, p.(Arg3719His) | 1 | — | — | — | — | — | 5 |
| c.12295-3 T>A | — | — | 1b | — | — | — | 8 |
| c.12575 G>A, p.(Arg4192His) | 4 (1 hom) | — | 1c (hom) | — | — | — | 5, 8, 23, 26 |
| c.13010C>T, p.(Thr4337Met) | — | 2 | — | — | — | — | 5, 35 |
| c.13316C>T, p.(Thr4439Ile) | — | 5 | — | — | — | — | 8, 21, 46 |
| c.14426C>T p.(Thr4809Ile) | — | 3 | — | — | — | — | 8, 36 |
Numbering of USH2A variants has been assigned in accordance with NCBI Reference Sequence NM_206933.2. The complete list of references can be found in LOVD-USHBase.
a
A single heterozygous variant in MYO7A was also reported in this patient; *a homozygous (hom) variant in MYO7A was also reported in this patient.
b
After reviewing the clinical data, the patient was categorised as atypical due to adult onset of hearing loss (45 years old) and normal speech.
c
After reviewing the clinical data, the patient was categorised as atypical due to very mild, progressive hearing loss.