Abstract

Study Design: Retrospective
Purpose: Phenotypic variations of Cone dystrophy
Methods: Visual and retinal examination, Fundus autofluorescence, Optical Coherence Tomography(OCT), Electroretinography(ERG) and whole exome sequencing were done. Set of identified mutations cloned and studied in HEK293T cells for their functional implications.
Results: Study population included 50 subjects, (35 males and 15 females) aged between 6-60 years. We observed varying range of visual acuity from 6/6 to counting fingers at 3m, normal fundus to atrophic changes, normal OCT features to loss of photoreceptors, ellipsoid and inter-digitation zone. Reduced or unrecordable photopic responses on ERG. Genetic mutations: PDE6C, CNGB3, CNGA4, CAorf37, KCNV2, CNGA3, MKKS were noted. Protein expression analysis had prognostic and therapeutic significance.
Conclusion:. Diverse phenotypic and genotypic profile observed, could potentially influence patient selection in future gene and cell therapy trials.