Genes for the immune system connected to schizophrenia

An international research team, including researchers from Karolinska Institutet, have used genome-wide mapping to identify 128 gene variants that can be connected to an increased risk of schizophrenia. The study has been published in the journal Nature and hopes to contribute new knowledge of immunological causes of mental illness.

Researchers from Psychiatric Genomics Consortium mapped 108 specific areas of the human genome, of which 83 have not been previously studied with regard to schizophrenia. In total, the study included genetic information from 36,989 patients and 113,075 control subjects.

Many of the identified gene variants that may be connected to an increased risk of schizophrenia are, not unexpectedly, of importance for the functioning of the brain. But the researchers have also found genes expressed in tissue that is important to the immune system, which according to the researchers support the assumption that there may be immunological causes underlying schizophrenia.

“For example, it is interesting to note that we were able to see an association with several genes involved in glutamate neurotransmission. This creates exciting openings for new forms of treatment,” says Christina Hultman, Professor of Psychiatric Epidemiology at Karolinska Institutet and one of the research team leaders behind the study.

The Psychiatric Genomics Consortium gathers researchers from 80 academic institutions in 25 countries around the world and with aims of studying genetic connections and causes relating to psychiatric disorders, such as ADHD, Tourette's syndrome, anorexia, bipolar disorder and schizophrenia. The research collaboration is led by Professor Patrick Sullivan, who was recently recruited to Karolinska Institutet. An important portion of the research materials of this study in Nature also come from Karolinska Institutet. The work has been financed by grants from, amongst others, the National Institute of Mental Health, philanthropic donations, the Swedish Research Council.

Publication

Biological insights from 108 schizophrenia-associated genetic loci
Schizophrenia Working Group of the Psychiatric Genomics Consortium
Nature online 22 July 2014, doi:10.1038/nature13595.