NIH researchers, working with colleagues abroad, have identified a new gene, UBAP1L, that contributes to a subgroup of IRDs. IRDs damage the retina of the eye, posing risks to vision that affect more than 2 million people across the globe. Each disorder is rare, which creates challenges for gathering enough data to inform analysis and potential clinical trials. The research was published online in JAMA Ophthalmology.
Through a focused analysis conducted on six unrelated patients, scientists concluded that the UBAP1L gene was indeed associated with various types of retinal dystrophies. Such conditions included maculopathy, which would occur in the macula, therefore affecting central vision; cone dystrophy, which would influence cone cells in charge of color vision; and cone-rod dystrophy that would affect both the cone and the rod cells which were used at night. Participants were reporting onset in early adulthood of features of retinal dystrophy, with severe impairment of vision established in late adulthood.
Dr. Bin Guan, chief of the Ophthalmic Genomics Laboratory at NIH’s National Eye Institute (NEI) and senior author of the report, said, “The patients in this study exhibited signs and characteristics that are similar to other IRDs, but the cause for their condition was unclear. Now that we have pinpointed the gene responsible for disease, we can now explore how the mutation in the gene leads to disease and, hopefully, work towards a cure.”
The discovery of a new UBAP1L gene joins the growing ranks of more than 280 genes known to be associated with this diverse array of diseases. Co-senior author and ophthalmologist at NEI, Dr. Laryssa A. Huryn, said that this is important because, “genetic testing is increasingly important for patients with retinal dystrophy, and these findings underscore the importance of the synergy between clinical and laboratory efforts to advance our understanding of retinal diseases.”
Genetic study on the six patients resulted in the detection of four variants of the UBAP1L gene, which encodes a protein, albeit one with substantial retinal cell expression, especially retinal pigment epithelium and photoreceptors. The function of this particular gene should be explored deeper with further study, although the preliminary findings thus far have indicated that it produces non-functional proteins because of these detected variants.
Notably, the genetic variants seem to be geographically localized; indeed, five of the six families come from South or Southeastern Asia or Polynesia – regions which have been relatively underrepresented in genetic studies. This important work was co-led by investigators at Moorfields Eye Hospital and University College London, further underscoring the collaborative nature of the work.
