Scientists have identified a specific gene they believe could be a key player in the changes in brain structure seen in several psychiatric conditions, such as schizophrenia and autism.



The team from Cardiff University’s Neuroscience and Mental Health Research Institute has found that the deletion of the gene CYFIP1 leads to thinning of the insulation that covers nerve cells and is vital for the smooth and rapid communications between different parts of the brain.



The new findings, published in the journal Nature Communications and highlighted in the journal Nature Reviews Neuroscience, throws new light on the potential cause of psychiatric conditions and could ultimately point to new and more effective therapies.



Though there are a number of genetic changes that can alter the risk of psychiatric disorders, one prominent change is called Copy Number Variants (CNV) and involves the deletion of bits of DNA.



Specifically, a CNV is where DNA is deleted from one of the chromosome pairs.



Work done in the world-leading Medical Research Council Centre for Neuropsychiatric Genetics and Genomics at Cardiff has shown that people who have these deletions of DNA have a much higher chance of psychiatric disorder but as the deletions often contain many genes, it has so far been a mystery as to exactly which genes contribute to the increased risk.



In their study the team focussed on the deletion of one specific gene, CYFIP1, located in a precise location of chromosome 15, known as 15q11.2, which had already been identified by the same team as an area with links to the biological abnormalities associated with psychiatric disorder.



Using cutting-edge methods and growing brain cells where one copy of CYFIP1 was missing, the team were able to show that this was linked to abnormalities in myelin - an insulating layer or sheath that forms around nerves in the brain.



Moreover, the team were able to trace these abnormalities back to specific brain cells called oligodendrocytes which are responsible for producing myelin sheaths.



First author of the study Ana Silva, who carried out the work with colleagues as part of her PhD studies, supported by the Wellcome Trust, said: “What surprised us most was how much of the 15q11.2 deletion effects could be explained by a single gene effect.



“We know that the risk of suffering from a psychiatric condition is influenced by a whole host of factors related to both the physical and social environment and our genetic make-up.