Not so long ago gene therapy was considered in the realms of science fiction. Remarkable progress has been made in the past 15 years, and the first ocular gene therapy to treat a rare inherited retinal disease called Leber congenital amaurosis due to mutations in the RPE65 gene has now been approved by the National Institute for Health and Care Excellence (NICE) for use as a treatment. The first patients in the UK have undergone this treatment on the NHS. This brings gene therapy firmly into the arena of clinical care, making it important for optometrists to have a basic understanding of genetics and gene therapy. This article will help with answering patient queries, managing patients and appropriate referrals.