Recently, a team of Yale researchers wanted to understand how genetic mutations in patients with Rett syndrome resulted in neurological issues. Using a unique type of genetic testing, researchers were not only able to understand the impact, but they were able to determine an experimental drug (JQ1) that might act as an effective treatment. Read the full study findings in Molecular Cell.
When Yale researchers began their study, they wanted to understand one crucial detail: how MECP-2 gene mutations caused poor neuronal function in patients with Rett syndrome.
To start, researchers used embryonic stem cells to build a human brain organoid with a MECP-2 mutation. For context, organoids are basically 3-D cell cultures that act as a miniaturized version of a human organ. While analyzing these organoids, researchers discovered brain cell abnormalities.
The genetic mutation most impacted interneurons. According to the Queensland Brain Institute, interneurons:
connect spinal motor and sensory neurons. As well as transferring signals between sensory and motor neurons, interneurons can also communicate with each other, forming circuits of various complexity.
So, interneurons play a role in inhibition, reflexes, and neuronal communication with the central nervous system. Interrupting this communication can lead to some of the neurological issues seen in patients with Rett syndrome.
Next, researchers examined different compounds to see if any drugs could potentially reverse or improve these symptoms. They found JQ1, an experimental cancer drug. After testing JQ1 on mice models, they found that mice who received the drug lived 2x as long as those who did not. While more research is needed, this shows promise in the ability to correct abnormalities in brain cells.
Rett syndrome is a genetic disorder which causes severe neurological effects. But while there are genetic mutations, the condition is not inherited; rather, these mutations usually occur spontaneously. It is extremely rare for males to have Rett syndrome. However, the disorder affects one out of every 10-15,000 females. The disorder is often fatal by early to mid-teens.
Symptom onset usually occurs between 6-18 months old. These include:
- Muscle weakness and “floppiness”
- Slowed brain growth and a small head
- Difficulty breathing
- No ability to speak or comprehend language
- Social anxiety
Learn more about Rett syndrome.