Study across ethnicities identifies new genes carrying Schizophrenia risk

New Delhi: Researchers have identified two previously unknown genes linked to schizophrenia and newly implicated a third gene as carrying risk for both schizophrenia and autism. Their study may also point to new therapeutics, it said.

The schizophrenia risk conferred by these rare damaging genes is maintained across ethnicities, the multi-centre study led by the Icahn School of Medicine at Mount Sinai, US, demonstrated.

The findings are published in the journal Nature Genetics.

Affecting about 1 in every 100 people in how they think, feel and behave, schizophrenia is among the most serious mental illnesses. The affected appear to have lost touch with reality, proving to be distressing for them and their close ones.

According to the study, the investigators found the two risk genes, SRRM2 and AKAP11, by comparing the gene sequences of people with schizophrenia to those of healthy controls.

The meta-analysis involved existing datasets totalling up to 35,828 cases and 107,877 controls, said the study which claimed to be the first known work of its kind studying schizophrenia across ethnicities.

It said that this study was built upon another recent study that identified 10 risk genes for schizophrenia, conducted in people with predominantly white European ancestry.

"By focusing on a subset of genes, we discovered variants that could potentially lead to new medicines for schizophrenia," said lead author Dongjing Liu.

"Also significant is that by studying people of various ancestral backgrounds, we found that rare damaging variants in evolutionarily constrained genes confer a similar magnitude of schizophrenia risk among those different populations and that genetic factors previously established in predominantly white people have now been extended to non-whites for this debilitating disease," said Liu.

The third gene flagged in the study, PCLO, was previously implicated in schizophrenia but is now identified as having a shared risk for schizophrenia and autism, the study said.

This finding raises a question about how we think about brain diseases as a whole, suggested Alexander W. Charney, a co-senior corresponding author of the study and associate professor at Icahn Mount Sinai.

"It's been known that there are genetic components shared among illnesses. Clinically, genes could look different in the same family.

"The same variant in the same family may cause autism in one family member and schizophrenia in another.

"The idea of the same gene having different manifestations is very interesting to us, as it could be useful when it comes to treating people in the clinic," said Charney.

The researchers caution that not every patient has a rare damaging variant in the identified schizophrenia genes.

The disease is multifactorial and there is no single factor.