The Biodonostia Institute is studying the genetic mutations that could be responsible for retinitis, a term used to describe a number of rare diseases that all lead to a progressive loss of visual acuity, and the genetic origin of the disease, although the hereditary patterns may differ.

Using the database compiled by the Gipuzkoa Begisare Association of Retinitis Pigmentosa Patients, the research group led by the neurologist Adolfo López de Munain at the Biodonostia Institute, together with the Ophthalmology Department at the Donostia Hospital, started the clinical part of this study, which also involves an epidemiological and molecular analysis of a sample of more than 200 patients, some two years ago.

The first results of this study, in which researchers from the University of Washington in St. Louis are also participating, show that “at least three previously known genetic mutations are found in a significant number of chromosomes”, in other words a significant number of retinitis patients have such a mutation. These results must be validated, however, as only five genes have been studied in each patient to date.

“We decided to analyse three genes that, due to their frequency, were highly likely to allow us to find something and a further two that were of interest due to the availability of animal models”, explains Javier Ruiz. Ruiz's work involves testing experimental gene correction therapies for retinitis using animal models, and he notes that “our results to date suggest that one of the genes found is one of those in the animal models”.

A further important aspect of this project concerns the work undertaken in the field of cell reprogramming, whereby cells from affected patients are extracted from a part of the body other than the retina, but whose genetic code contains the mutation that causes retinitis, then manipulated to obtain “a cell model similar to the retina which can be studied in vitro to test the possible success of a therapeutic strategy and to try to understand the process at a pathophysiological level”.