Large-scale genetic analysis uncovers new insight into how common DNA differences play a role in the development of rare brain conditions.
 
The combination of common DNA differences can help explain why some people have a rare neurodevelopmental brain condition without a specific, single genetic mutation causing it. Researchers from the Wellcome Sanger Institute and collaborators looked at data from thousands of children with rare neurodevelopmental conditions and their parents to investigate how common DNA differences contribute to these conditions.
 
The study, published today (20th of November) in the journal Nature, extended a 2018 study by the same group showing that while their overall role is small, common genetic differences can help to explain why some people have a neurodevelopmental condition. Specifically, these common DNA differences overlap with those that are more likely to be found in people affected by later-onset conditions, such as depression and schizophrenia.
 
In addition, this new study found that common genetic differences, when present in the parents, may affect the chance of their child developing a neurodevelopmental condition, even if the child does not inherit those genetic differences directly. However, more research is needed to fully understand this.