New gene linked to glaucoma

An international team of researchers has discovered a new gene linked to one of the major causes of glaucoma. A common variation in the gene known as CACNA1A increases the risk of developing ‘exfoliation syndrome’ which can lead to high pressure in the eye.

Exfoliation syndrome is an age-related condition in which a build-up of material blocks the eye’s drainage system. Usually, the eye stays at a constant pressure by continuously producing fluid while an equal amount of fluid drains out of the eye.

However, if the drainage system is blocked, pressure in the eye can build-up and damage the optic nerve (the specialised cable that sends visual signals from the eye to the brain) leading to irreversible sight loss. This is known as ‘primary open-angle glaucoma’.

Common to all ethnic groups

The researchers looked at the whole genome of people from 17 countries (more than 8,000 with exfoliation syndrome and around 22,000 controls). They found that the variation in CACNA1A that’s linked to exfoliation syndrome is common to people of all ethnic groups. They also confirmed that the gene LOX1, which has previously been linked to exfoliation syndrome, only increases risk in some ethnic groups.

Our Research Director Dr Dolores M Conroy said: “This is very interesting work. We know that glaucoma is one of the major causes of severe sight loss worldwide, and that exfoliation syndrome is a significant risk factor.

“We also know that CACNA1A is involved with calcium and the way that cells communicate with each other, which opens up new possibilities for drug treatments that target this system. We look forward to future work to find out exactly how this genetic variant leads to exfoliation syndrome.”

The results were published in Nature Genetics.