Irish research helps landmark studies identify genes that raise risk of schizophrenia

Russell Crowe as John Nash in A Beautiful Mind. The mathematician struggled with paranoid schizophrenia following his diagnosis in the 1950s. Photo: Universal Studios/Reuters

Seán Duke

April 07 2022 02:30 AM

The genes that put people at risk of developing schizophrenia have been identified in landmark global studies which included input from Irish scientists and thousands of Irish patients.

Researchers identified 287 regions on the human genome that increase the risk of schizophrenia as part of the Psychiatric Genomics Consortium, of which Trinity College Dublin (TCD) is a member.

In a parallel study, researchers identified 10 further genes which increase a person’s risk of schizophrenia by up to twentyfold, as part of the SCHAEMA Consortium. The two studies are published together in the journal Nature.

The Irish research input into the decades-long, global research effort involving 300,000 patients – 3,000 of them in Ireland – was led by Professor Aiden Corvin of the psychiatric research group at TCD, and Dr Derek Morris, director of the Galway Neuroscience Centre at NUIG.

Dr Morris said some of the medications currently used for schizophrenia “were discovered accidentally 50 or 60 years ago, and there’s been relatively few new medications and treatments that have become available since that time”.

“If you compare that to other common illnesses, that’s a pretty shocking situation,” he said.

Prof Corvin, a psychiatrist at St James’s Hospital in Dublin, said new drugs for schizophrenia are badly needed.

“We have psychological therapies that help to some degree, but a significant proportion of our patients – about one-third – don’t respond at all,” Prof Corvin said.

“People with schizophrenia have a life expectancy that’s about 15 years less than general and many are very significantly impaired – not able to work.”

Schizophrenia, which is thought to be about 80pc genetic, affects 1pc of the population, which in Ireland amounts to 50,000 people, two thirds of them men.

Dr Morris said the findings show “abnormal neuron function in schizophrenia affects many brain areas, which could explain its diverse symptoms, which can include hallucinations, delusions and problems with thinking clearly”.

The studies suggest better understanding of the biology of how electrical messages, which travel back and forth across the synapses between the brain’s neurons, are disrupted is key to discovering more effective schizophrenia drugs.

The studies both found genes involved in schizophrenia overlapped with other brain disorders like autism and epilepsy. The scientists now believe there may a “spectrum of risk”, where the more damaged certain shared genes are, the more severe the brain disorder.