New research points to schizophrenia risk
26 July 2010
A study published in the journal Human Molecular Genetics led by Dr Evangelos Vassos and colleagues from the Institute of Psychiatry (IoP) at King’s has published data which estimates the risk of schizophrenia in human DNA.
The development of new laboratory methods to investigate the genome, which is composed of our hereditary material, DNA, has allowed a detailed investigation of previously invisible duplications and deletions, and their role in the illness. The team believes that these rare deletions and duplications of DNA are indicators of risk of schizophrenia.
An average individual has copy number variants (CNVs) in a genome, where sections of DNA are either missing (there is only one copy) or duplicated (there are more than the normal two copies). Most of these seem to do no harm, but rare CNVs have been identified as being important indicators for common complex brain disorders, including schizophrenia, autism, epilepsy and intellectual disability. However, the proportion of individuals who exhibit clinical symptoms has not been properly estimated until now. The researchers believe this is important to measure in order to develop CNV testing for diagnostic purposes.
Dr Evangelos Vassos, Professor David Collier and colleagues used a novel statistical method developed by Professor Cathryn Lewis, to examine CNVs for schizophrenia. Dr Vassos said: 'Schizophrenia is a common, complex and severe mental illness, but its causes are still mostly unknown. The risk of developing schizophrenia for carriers of these mutations is between two and seven per cent meaning they are some of the strongest genetic risk factors ever identified for common mental illness. Although they are individually rare, each affecting fewer than one in 200 patients, collectively they have a significant risk on disease burden.'
‘Penetrance for copy number variants associated with schizophrenia’ is published in the July edition of Human Molecular Genetics to read the paper in the full, please follow the link.