Gene causing schizophrenia identified utilizing Finnish sample collections

21.3.2016
An international research consortium has identified a gene which, if damaged, multiplies the risk of schizophrenia 35-fold. Abnormal forms of the SETD1A gene are rare, and only responsible for a fraction of schizophrenia cases – it is estimated that one in every thousand cases is attributable to the gene. However, the link between the gene and schizophrenia is exceptionally strong, as every subject who carried an abnormal version of the gene was diagnosed with either psychiatric or neuropsychiatric disorders.

The results were published on 14 March 2016 in the esteemed journal Nature Neuroscience. The research group that made the discovery features Finnish members from the University of Helsinki, the University of Oulu, the Finnish National Institute for Health and Welfare, as well as Boston’s Stanley Centre at the Broad Institute of MIT and Harvard.

Due to the rarity of the gene abnormalities, the research group had to use several extensive collections of samples from the UK, Sweden and Finland. Samples collected in northern Finland proved to be the most valuable, as they were accompanied by the most exact medical background information.

“This study is another excellent example of the value of Finnish sample collections and the resulting genetic information for genetic research,” states Research Director Aarno Palotie from the University of Helsinki’s Institute for Molecular Medicine Finland (FIMM), who ran the Finnish branch of the study.

“We have taken great strides in analysing the genetics of schizophrenia during the past few years, and have already identified more than one hundred gene mutations that increase susceptibility to this difficult disease. However, most of these mutations are common, and individually do little to increase the risk of illness. The gene and its abnormalities identified in our study constitute the first known example of a single gene whose incorrect function causes schizophrenia.”

The SETD1A gene regulates the expression of many other genes, like a conductor of a genetic orchestra. It can thus be assumed that disorders in this gene would significantly hamper normal cell function.

The research group points out that even though abnormalities in the gene identified in this study only explain a fraction of all cases of schizophrenia, the discovery reveals new, valuable perspectives on how the disease develops. Ideally, discovering previously unknown biological factors that lead to the onset of schizophrenia can generate new opportunities for drug development.

The Institute for Molecular Medicine Finland and the National Institute for Health and Welfare have recently launched the SUPER research project funded by the Stanley Center, intending to further determine the hereditary aspects of psychotic illnesses.

 

Further information:

Professor Aarno Palotie, phone: 041 501 5915, email: aarno.palotie@helsinki.fi

Article: Tarjinder Singh et al. (2016). Loss-of-function variants in SETD1A are associated with schizophrenia and developmental disordersNature Neuroscience.