The genes were identified through a meta-analysis comparing gene sequences of 35,828 people with schizophrenia to 107,877 people without the condition.
The study builds on a report published last year that identified 10 genes with rare variants that are directly tied to schizophrenia risk. But that study, like most prior genetic analyses on psychiatric illnesses, was done on the DNA from people of European ancestry.
About 40% of the genetic samples included in this new work came from people of non-European ancestry, which researchers say makes it the most ethnically diverse schizophrenia genetics study to date.
Based on the findings, researchers concluded that the schizophrenia risk conferred by the rare genetic variants found on the new genes they discovered and on those previously identified is conserved across ethnicities.
The new genes, SRRM2 and AKAP11, contain rare protein-truncating variants (PTVs) that investigators say could be the cause of schizophrenia in some patients. The results could have significant implications for drug development.
“It’s not curing the illness, but it is taking us a step closer so that we’re able to say that this may be the cause of the illness in a particular patient,” senior investigator Alexander Charney, MD, PhD, associate professor of psychiatry, genetics and genomic sciences, neuroscience, and neurosurgery, at Icahn School of Medicine at Mount Sinai, New York, said in an interview.
The findings were published online in Nature Genetics.