The researchers were able to identify two specific mutations within the GPT2 gene, with their findings backed up by other research groups linking mutations in the same gene to a neurological disease found in other families. To establish how the altered GTP2 gives rise to the disease, the researchers then created both human cells and mouse models where they introduced the mutations, and found that developing mice showed reduced neural and brain growth. When they looked in closer detail, they found that the neurons in affected mice had fewer synapses, which are the connections between brain cells that make up brain circuits.
“This is a clear, new neurogenetic disorder due to mutations in GPT2,” explains Dr Eric Morrow, co-author of the paper describing the as yet unnamed disease in the Proceedings of the National Academy of Sciences, in a statement. “In addition to the relevance this has to the diagnosis of developmental disorders, and potentially therapeutics, it is also a window into how the brain develops and how the brain functions.”
Not only that, but the enzyme GPT2 is also related to the amino acid glutamate, a neurotransmitter that regulates how brain cells interact. “To find a glutamate metabolizing enzyme that is associated with a brain disease is an opportunity to understand how that neurotransmitter might work or be modulated,” says Morrow. It is hoped that if the condition is diagnosed in children early enough, there could be some way to prevent its progression. Researchers are now trying to learn as much as they can about the disease and how it can be prevented.