[ad_1]
Over the years, many studies have identified a plethora of genes associated with Autism Spectrum Disorder (ASD). Although we have a general idea of the behavior of these genes, it has been difficult to study what they do at the cellular level.
Researchers at the University of California at San Francisco (UCSF) have now mapped the expression of genes in isolated neurons taken from children with ASD, revealing potential differences to understand why some of these cells have so much trouble connecting.
Autism is not described as a specter for nothing. Not only does it vary in severity, but its range of characteristics makes it an incredibly complex condition that we still have trouble understanding.
Yet, despite the complex mix of genes and environmental influences thought to be responsible for ASDs, some factors remain consistent. An example is the conversation of certain genes that express themselves during neurological development.
This genetic chatter, called a transcriptome, was measured in tissues taken from areas such as the frontal cortex and the cerebellum, revealing significant differences between the brains of people diagnosed with ASD and those who did not.
Collecting transcriptomes from tissue samples is like eavesdropping on the buzzing buzz of a crowd at a party. It has its uses in the diagnosis of ASD, but what the researchers really wanted was to hear what each client had to say.
Since autism may be partly caused by neurons that have trouble connecting as might be expected, it is important to describe these unique genetic translations at the cellular level if we want to put point of effective treatments.
"Identifying the genetic changes that occur at conception or in the uterus is important for understanding the causes of autism, but it is unlikely that this information will provide useful therapeutic targets," says neurologist Arnold. Kriegstein.
"If we want to be able to offer treatments to these children when they come to our attention, it is the altered brain circuits that we will have to face."
Extracting a transcriptome from a targeted cell is not a walk in the park, which is why we have never seen it before. The UCSF science writer, Nicholas Weiler, uses the wonderfully colorful depiction of teasing neurons as "playing Jenga with Jell-o".
Thus, rather than trying to unravel a knotted mess, the team extracted RNA isolated nuclei from neurons in frozen cortical tissue samples collected during the autopsy of 15 children and adolescents with a diagnosis of ASD and 16 others without. Then, they identified the types of cells they were examining based on their gene expression signatures.
Since epileptic seizures tend to be more common in autistic children, tissue samples taken from people with epilepsy have also been analyzed for comparison.
About 100,000 nuclei later, the team could identify differences in the expression of genes associated with communication between neurons across their synapses.
Specifically, the individual cells that held these difficult conversations were in the upper layers of the neocortex, including projection neurons extended to other regions, as well as microglia – non-signaling defensive cells that manage connectivity.
The comparisons also confirmed the existence of a relationship between the severity of ASD and the degree of expression in the key genes of these cell types.
Now that researchers have a better idea of brain cells that significantly express autism genes, future studies should help determine more precisely what they do and why the brains of people with Alzheimer's disease. TSA is connected in the same way.
More importantly, it could also lead to therapies for people who are struggling to cope with some of the most difficult features of the disease.
"It was very exciting to see such a sharp convergence on specific cell types that appear to have been altered in all these patients," said molecular biologist Dmitry Velmeshev.
"This gives hope that someday there could be a broadly applicable treatment for many patients with the disease."
This research was published in Science.
[ad_2]
Source link