Schizophrenia, a mental disorder marked by distorted thoughts, hallucinations and delusions, affects about one in every 100 individuals worldwide but the biological mechanisms behind the condition is poorly understood. As a result, available treatments for the illness only address its symptoms and many do not respond well to medications.
Findings of a new study, however, could pave way to better and more effective treatments for the disease. In one of the largest studies ever conducted to investigate the genetic origins of schizophrenia, scientists have found 83 new gene variants that are associated with the disease.
For the study published in the journal Nature on July 22, hundreds of researchers from the Psychiatric Genomics Consortium (PGC), which analyzes genome-wide genetic data for bipolar disorder, schizophrenia, major depressive disorder and other psychiatric disorders, analyzed the genes of over 150,000 individuals, 36,989 of whom had schizophrenia.
Because the study pooled genetic samples that are primarily those of individuals who were diagnosed with schizophrenia, the researchers were able to identify 108 genetic locations, also known as loci, where the DNA sequence of schizophrenic individuals differ from those who do not have the mental disorder. Eighty-three of these 108 loci have just been identified to be tied to schizophrenia.
"We identify 128 independent associations spanning 108 conservatively defined loci that meet genome-wide significance, 83 of which have not been previously reported," the researchers wrote. "The findings include molecules that are the current, or the most promising, targets for therapeutics, and point to systems that align with the predominant aetiological hypotheses of the disorder."
Study researcher Michael O'Donovan, from Cardiff University in the United Kingdom, said that the identified loci were found near or in genes that are believed to have links with schizophrenia and other mental disorders. The researchers also noted that the loci involve genes associated with the immune system and are involved in the regulation of the neurotransmitter dopamine. Some are also associated with smoking.
O'Donovan said that he hopes that their findings could pave way for new treatments that could provide better outcomes for patients with schizophrenia.
"The fact that we were able to detect genetic risk factors on this massive scale shows that schizophrenia can be tackled by the same approaches that have already transformed our understanding of other diseases," O'Donovan said adding that the findings of the large-scale study can potentially lead to the development of new schizophrenia treatments which has stalled in the last six decades.