Scientists investigate role of gut bacteria in sight loss

Researchers from the UK and China have found gut bacteria in the eyes of patients with a specific genetic mutation that leads to blindness

A petri dish is displayed on a black background. On the surface of the petri dish, there are white bacterial growths

A new study published in Cell has outlined how gut bacteria were found in the eyes of patients with a gene associated with retinal degeneration.  

The CRB1 gene is the cause of 10% of Leber congenital amaurosis cases and 7% of retinitis pigmentosa cases worldwide.

In experiments in mice, the researchers from Sun Yat-sen University and UCL Institute of Ophthalmology discovered that the CRB1 gene plays an important role in maintaining the integrity of the gastrointestinal tract.

When there is a mutation in this gene that weakens its expression, bacteria in the gut can move through the body into the eye – leading to lesions in the retina that cause sight loss.

The research team found that treating the mice with antibiotics was able to prevent sight loss.

Professor Richard Lee, of UCL Institute of Ophthalmology and Moorfields Eye Hospital NHS Foundation Trust, said the findings have implications for transforming the treatment of CRB1-associated eye diseases.

“We hope to continue this research in clinical studies to confirm if this mechanism is indeed the cause of blindness in people, and whether treatments targeting bacteria could prevent blindness,” he said.