Clinical Evidence for the Importance of the Wild-Type Allele in the Phenotypic Expression of RP11.

-associated retinopathy (RP11) is a common form of autosomal dominant retinitis pigmentosa (adRP) that exhibits wide variation in phenotype ranging from non-penetrance to early-onset RP. Herein, we report inter-familial and intra-familial variation in the natural history of RP11 using multimodal imaging and microperimetry. Patients were recruited prospectively. The age of symptom onset, best-corrected visual acuity, microperimetry mean sensitivity (MS), residual ellipsoid zone span and hyperautofluorescent ring area were recorded. Genotyping was performed using targeted next-generation and Sanger sequencing and copy number variant analysis. mutations were found in 14 individuals from seven unrelated families. Four disease patterns were observed: (A) childhood onset with rapid progression ( = 4), (B) adult-onset with rapid progression ( = 4), (C) adult-onset with slow progression ( = 4) and (D) non-penetrance ( = 2). Four different patterns were observed in a family harbouring c.267del; patterns B, C and D were observed in a family with c.772_773delins16 and patterns A, B and C were observed in 3 unrelated individuals with large deletions. Our findings suggest that the RP11 phenotype may be related to the wild-type allele rather than the type of mutation. Further studies that correlate in vitro wild-type allele expression level with the disease patterns are required to investigate this association.