“We use the information to get a better understanding of where genes are active and how that relates to mental health disorders,” Professor Derks said.
“By linking this to gene expression studies performed previously we can get a better understanding of which specific genes are responsible and what are they doing – are they too active or not active enough.”
Specifically, the researchers identified 275 genes which interact to create a risk of schizophrenia, 13 genes which interact to raise the risk of bipolar disorder, 31 genes involved in depression and 12 for ADHD.
They also did extensive testing on where in the body the various genes were found, revealing 137 (41 per cent) were found solely in brain tissue while 24 per cent of the genes were detected in the easily accessible blood tissue.
“So we have a good understanding of all that now, and the next step is to see if we have any drugs which can target these genes,” Professor Derks said.
Beyond Blue lead clinical adviser Grant Blashki said being able to target specific genes with medication would be a major step forward for mental health treatment.
“We’ve known for a while now that mental illness is caused by both nature and nurture, but studies like this are helping us to understand the nature side of things,” Dr Blashki said.
“Very often doctors will choose the best medication but there’s still a degree of trial and error, and variation between individuals.
“My hope is this sort of research is going to help us be more nuanced and more targeted so we get people on the treatments which will be most beneficial for them.
Dylan Reid did a world tour on motorbikes with his brother in 2015-16 to raise money for mental health research, after their sister Heidi died by suicide in 2011 aged 27.
Mr Reid also welcomed the breakthrough, saying the current methods of treating mental health were inadequate.
“I’m not having a dig at the doctors, they’re doing the best they can with the tools they have. The point is the tool they have are pretty rubbish,” he said.
“What happens is you have people getting medicated that don’t need it and vice versa.
“I feel like the stigma of mental illness is starting to be sorted out … the next step is understanding the science.
Mr Reid said fundraising for mental health projects had opened his eyes to how little money was being allocated to research in the field, and how important it was to direct that funding where it was needed.
“It’s the pie in the sky ideas, the left-field ideas – that’s where the breakthroughs are going to be,” he said.
“We’re not going to make breakthroughs doing what we’ve always done.”
However, Dr Blashki did sound a note of caution, pointing out any medical issue surrounding genetics needed to be treated delicately.
“We as a society have to make sure we keep up with the ethical social and privacy issues that are undoubtedly going to arise from this sort of research,” Dr Blashki said
“With genetic tests we need to be pretty cautious about interpretation, privacy, implications for family members, and be very careful about how we use this information as it becomes more specific.”
In addition to looking at more targeted treatments for the four mental conditions in this study, the researchers also now hope to look at the genetic causes of more disorders, including obsessive compulsive disorder, substance abuse and anorexia.
The findings have been published on Tuesday in the journal Nature Genetics.
Stuart Layt covers health, science and technology for the Brisbane Times. He was formerly the Queensland political reporter for AAP.