SINGAPORE — In the largest genomic study published on any psychiatric disorder to date, researchers from the Institute of Mental Health (IMH) and the Genome Institute of Singapore (GIS) have identified genetic markers that will enable better and early identification of those who might develop schizophrenia.

A disorder that has seen little development in drug treatment options in the past 60 years, schizophrenia affects approximately one out of every 100 people worldwide.

The latest findings by the researchers point to biological mechanisms and pathways that may underlie the disorder, and could lead to new approaches to treat it.

“With the new genetic loci identified, investigators can now further examine the functions of these genes especially related to the communications between brain neurons (cells) and their relationship with brain changes, cognition, clinical symptoms and daily functioning of the patients.

“A combination of this information from future studies can potentially allow for better detection of the illness, design of new treatments and monitoring of response to treatment,” explained Adjunct Associate Professor Sim Kang, one of the researchers from IMH’s Research Division.

He added: “Local data suggest that treated individuals are found with improvements of symptoms, and are able to engage in gainful employment, and there are significant improvements in daily functioning when the condition is detected and treated early.”

Medication currently available on the market treats only psychosis, which makes up one of a multitude of symptoms of the disorder, with other debilitating symptoms such as cognitive impairments left untreated. This is partly due to the fact that the biological aspect of the disorder had not been fully understood.

The researchers looked at more than 80,000 genetic samples from individuals with and without schizophrenia, and found 108 specific marker locations — of which 83 were previously thought unassociated with the disorder — in the genome. They also found evidence for a previously-hypothesised theory of a link between the disorder and genes in the immune system. This suggests that other loci uncovered may point to additional targets for therapy in the future.

The findings of the study were published online in scientific journal Nature yesterday. Professor Jianjun Liu, Deputy Director of Research Programmes at GIS — an institute under the Agency for Science, Technology and Research — and head of the genetic study programme of the project, said that the study, which took several years of work, was a “great demonstration that large-scale genetic association study is a powerful tool for understanding disease genetic susceptibility and revealing novel biological insight into disease mechanism”.

The researchers were part of the Schizophrenia Working Group of the Psychiatric Genomics Consortium (PGC), and the study was part of the five-year Translational Clinical Research in Neuroscience, which is funded by the National Research Foundation. The PGC is an international, multi-institutional collaboration founded in 2007 to conduct broad-scale analyses of genetic data for psychiatric disease.