According to a story from EurekAlert! an international team of scientific researchers have made an unusual discovery. The team found in the course of their studies that dietary supplementation with the amino acid L-serine was able to successfully improve the neuron function of a patient with atypical Rett syndrome. This patient presented with an unusual mutation affecting the GRIN2B gene. This gene codes for a certain glutamate receptor.
About Rett Syndrome
Rett syndrome is a brain disorder that becomes evident early in the lives of its female patients. The disease is typically caused by a genetic mutation that affects the MECP2 gene. This gene is found on the X chromosome. Boys who have this mutation die soon after being born, so Rett syndrome exclusively affects girls. It occurs as a spontaneous mutation in the vast majority of cases, and is rarely inherited from parents. Symptoms include sleeping issues, difficulty speaking, poor coordination, scoliosis, seizures, small head size, slow growth, and repetitive movements. There is no cure for Rett syndrome, and management focuses on maintaining function and alleviating symptoms. Life expectancy for patients is around 40 years. Death often occurs sponatenously, and is often linked to brainstem malfunction, gastric perforation, or cardiac arrest. To learn more about Rett syndrome, click here.
What This Discovery Means
While the discovery may not actually be particularly relevant to many Rett syndrome patients (whose disease is often linked to an entirely different mutation), the finding has the potential to open up a new field of therapeutic approaches for patients with similar mutations that have an impact on glutamathemic neurotransmission. The original goal of the research was determine the impact that the GRIN2B mutation was having; the scientists knew that it was causing Rett syndrome symptoms to appear, but they didn’t know why.
The team determined that the mutation caused a subtle change in just a single amino acid, which was enough to suppress the function of NMDA glutamate receptors. From this finding, the scientists theorized that supplementation of L-serine could compensate for the reduced receptor function. After 17 months of supplementation the Rett syndrome patient saw dramatic improvements in both motor and cognitive function, being able to complete motor tasks that would have been inconceivable previously.
A clinical trial with a greater number of patients is currently being organized to test the approach further.