New autism marker discovered in kids

autism
Credit: Pixabay/CC0 Public Domain

Why do so many children with autism often suffer from epilepsy? Northwestern Medicine scientists have discovered an important brain protein that quiets overactive brain cells and is at abnormally low levels in children with autism.

This protein can be detected in the , making it a promising marker to diagnose autism and potentially treat the epilepsy that accompanies the disorder.

Scientists knew when this gene is mutated, it causes autism combined with epilepsy. About 30% to 50% of children with autism also have epilepsy. Autism, which is 90% genetic, affects 1/58 children in the U.S.

Appropriately nicknamed "catnap2," the protein, CNTNAP2, is produced by the when they become overactive. Because the brains of children with autism and epilepsy don't have enough of CNTNAP2, scientists found, their brains don't calm down, which leads to seizures.

For the study, Penzes and colleagues analyzed the cerebrospinal fluid in individuals with autism and epilepsy, and in mouse models. Scientists have analyzed the cerebrospinal fluid from patients with Alzheimer's disease and Parkinson's disease to help diagnose disease and measure response to treatment, but this is the first study showing it is an important biomarker in autism.

The study will be published Dec. 17 in Neuron.

The new finding about CNTNAP2's role in calming the brain in and epilepsy may lead to new treatments.

"We can replace CNTNAP2," said lead study author Peter Penzes, the director of the Center for Autism and Neurodevelopment at Northwestern University Feinberg School of Medicine. "We can make it in a and should be able inject it into children's , which will go back into their brain."

Penzes' lab is currently working on this technique in preclinical research.

The level in the is proxy for the level in the brain, said Penzes, also the Ruth and Evelyn Dunbar Professor of Psychiatry and Behavioral Sciences at Northwestern.

When brain cells are too active because of overstimulation, they produce more CNTNAP2, which floats away and binds to other brain cells to quiet them down. The protein also leaks into the cerebrospinal fluid, where scientists were able to measure it. Thus, it gave them a clue for how much is produced in the brain.

Northwestern co-first authors are Lola Martin de Saavedra and Marc dos Santos.

More information: M. Dolores Martín-de-Saavedra et al, Shed CNTNAP2 ectodomain is detectable in CSF and regulates Ca2+ homeostasis and network synchrony via PMCA2/ATP2B2, Neuron (2021). DOI: 10.1016/j.neuron.2021.11.025

Journal information: Neuron
Citation: New autism marker discovered in kids (2021, December 17) retrieved 21 May 2024 from https://medicalxpress.com/news/2021-12-autism-marker-kids.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.

Explore further

When kids' autistic brains can't calm down

459 shares

Feedback to editors