By Chang Ai-Lien

RESEARCHERS at Singapore's National Neuroscience Institute (NNI) have developed a novel fly model of Parkinson's disease that could help speed up drug discovery efforts for the debilitating disorder.

There is no cure for Parkinson's, a progressive and degenerative neurological ailment that often impairs the sufferer's movements and speech.

An estimated six million people worldwide have the disease, including up to 7,000 in Singapore.

Its exact cause is unknown, although a significant number of Parkinson's patients have a mutation in a gene known as LRRK2, said the NNI in a statement.

LRRK2 is a complex protein with more than 2,500 amino acids.

One famous carrier is Google co-founder Sergey Brin, who revealed that he carries a mutation of the LRRK2 gene - called G2019S - that increases the risk of Parkinson's disease in some families.

His mother has the disorder as well as the mutated gene.

The NNI contributed to the discovery of another LRRK2 variant that is almost exclusive to the Chinese and Japanese populations, said the institute in a statement.

A person with this "Asian" gene variant has a two to three times higher risk of developing Parkinson's.

The institute said it had created the first fruit fly model of this variant.

And when they age, these flies have symptoms similar to those of their human counterparts.

For example, populations of brain cells that are similar to those affected in the human form of the disease start to die gradually in the fly's brain.

Older mutant flies also have difficulty moving.

Studying the flies could help unlock some mysteries that surround brain cell death in Parkinson's patients, said the institute.

The study, led by Associate Professor Lim Kah Leong, senior research scientist at the NNI-TTSH campus, together with Associate Professor Tan Eng King, senior consultant neurologist at the NNI-SGH campus, and the NNI Translational Clinical Research Programme team members, was published in last month's issue of The Journal of Neuroscience, a leading international neuroscience journal.

Both Prof Lim and Prof Tan are also faculty members at Duke-NUS Graduate Medical School.

An advantage of using fruit flies for such studies is that they are cheap, small and do not live long, which makes them ideal candidates for drug screening, explained Prof Lim.

"If we could be more modest about our hierarchy, evolutionary or otherwise, there is a great deal that we could learn from our so-called humble counterparts," he said.

The NNI has already begun drug screening efforts with the flies, and said it is in talks with some drug companies to see how to speed up the process.

The study is supported by SingHealth Foundation and the Singapore Millennium Foundation.

This article was first published in The Straits Times.

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