SINGAPORE - Local scientists, together with international collaborators, have discovered a gene mutation that plays a part in a rare form of glaucoma here.

The mutated CACNA1A gene was found to affect calcium transport channels, causing blockages in the interior of the eye that can lead to the disease.

This particular form, called exfoliation glaucoma, affects less than one per cent of Singaporeans.

A quarter of Singaporean Chinese people carry a mutated CACA1A gene which means their risk of developing exfoliation glaucoma is 40 to 56 per cent higher than a Singaporean Chinese person with the gene in its normal form.

About 28 per cent of Singaporean Indians carry the mutated gene and their risk of developing exfoliation glaucoma is 19 to 25 per cent higher than Singaporean Indians with the normal gene.

No Malay samples were involved in the study.

The Singaporean Chinese and Indian numbers were slightly higher than the global average of 25 per cent of people with the faulty gene.

"With this knowledge, we can now develop therapeutic solutions to address the calcium signalling function in the eye to reduce the risk of exfoliation glaucoma," said Professor Aung Tin Senior Consultant and Head of the Glaucoma Service at the Singapore National Eye Centre.

Another researcher who took part in the study, Dr Khor Chiea Chuen from the Genome Institute of Singapore, suggested that such eye drugs may come in the form of calcium blockers, similar to those that target the heart. But a suitable drug targeting the eye may take a decade or more to formulate.

The study involved more than 2,000 samples from Singapore and was part of a wider study that involved 8,400 people from 17 countries across all six continents.

Genes may also affect the risk of glaucoma. Those with a family history of glaucoma are advised to go for eye checks early, at about 50 years of age, so doctors can assess their risk and treat them early.