One of the fastest moving and most exciting areas in developmental neuroscience is neurogenetics. The key is to understand how genes produce the proteins that make up the brain and how they in turn affect behaviour. This week a study published in The New England Journal of Medicine looks at the role of a specific gene in Specific Language Impairment (SLI)- see study details here. The researchers have found that the gene CNTNAP2 is associated with performance on a non word repetition task which is a behavioural marker for SLI. The gene seems to have a role in brain development and more specifically in enrichment of frontal gray matter. I have to say I am really surprised by these findings. I tend to take the view that Professor Robert Plomin at the Institute of Psychiatry takes which is that genes are likely to be more general in their effects with genes likely to mainly effect several different brain areas and functions. This would make sense from a biological and evolutionary perspective. He and his colleague Yulia Kovas have written a good summary about these issues in our Child Neuropsychology book. My understanding is that language development is a very dynamic process involving many brain areas at first and then fixing in set areas. If these set areas are damaged language can still develop in different brain areas. I am not sure how damage to one area of the brain from birth due to genes would have such a specific effect. Also I would be amazed if this brain area affected by this gene just affected such a specific task as non word repetition- I am sure that it would affect other functions as well. The paper is however detailed in terms the genes involved, the brain areas they affect and the behaviours that are affected as a result. We will need to see whether the findings are replicated and whether they generalise. A previous very promising finding by the same research group which suggested that the FOXP2 gene was involved in language disorder proved to only relate to a few very unusual cases. Over the next few years expect to see increasing research into neurogenetics. Some of these findings are likely to challenge the way we understand child development. It should lead to a revolution in our understanding of child disorders and how to treat them. It is an exciting time for child neuropsychology.