According to researchers, chemical changes in the eye can lead to blindness in middle-age.
Their findings aid understanding of a genetic condition that causes sight loss for one in 3,000 people in the UK.
The team examined how changes in a gene - known as RPGR - can damage eye cells to cause a disorder known as X-linked retinitis pigmentosa - a chronic hereditary eye disease characterized by black pigmentation and gradual degeneration of the retina.
The condition is incurable and affects night and peripheral vision before gradually causing blindness in middle age.
The team from the University of Edinburgh took skin samples from two patients and transformed stem cells - which can change into any cell type - into light-sensing eye cells known as photoreceptors.
They compared these with cells from healthy relatives of the patients.
Photoreceptors - which decay in retinitis pigmentosa patients - differed in their fundamental structure when compared with those from family members.
Follow-up studies in mice identified key molecules that interact with RPGR to maintain the structure of photoreceptors.
When RPGR is flawed, the structure is compromised and photoreceptors cannot function correctly, leading to sight loss.
Lead researcher Dr Roly Megaw said that by furthering the understanding of the RPGR gene and its effects on photoreceptor cells, they hope that these findings bring them closer to developing a possible treatment for this devastating disease.
The research, which is presented on September 5 at the Eye Development and Degeneration 2017 conference in Edinburgh, appears in journal of Nature Communications. (ANI)