JUL 06, 2020 6:38 AM PDT

Learning More About How Folds Form in the Developing Brain

WRITTEN BY: Carmen Leitch

The folds or gyrification of the human brain are essential to its function, and improper folding has been linked to a variety of disorders including autism, epilepsy, and schizophrenia. Premature birth is a major risk factor for cerebral palsy and it's been associated with misfolding. But researchers don't know a lot about how these folds form or how the process goes awry. Now scientists have gained new insight into how folds develop in the brain of a fetus. In research reported in Cerebral Cortex, scientists have found genes that are connected to the development of both inward and outward folds.

Grey matter neurons in the outward folds (left) and inward folds (right), differences shown in red. . / Credit: RMIT University

The scientists used sheep, an animal model that is similar in some ways to the development of the human brain. They identified changes in gene expression and the shape of neurons as the folding occurred.

The co-lead researcher, RMIT University Associate Professor Mary Tolcos noted that there is no treatment for misfolding in the brain, and no diagnostic tests that can reveal a problem before it starts.

"We know folding happens in the second and third trimester of pregnancy and that all human brains fold along largely the same patterns. This suggests the process is heavily controlled by our genes but we're only starting to understand how - it's like having an intricately folded piece of origami that's missing the instructions. Our study is a critical step towards fully understanding those genetic instructions, by pinpointing which genes are linked with fold development," said Tolcos, an Australian Research Council Future Fellow at RMIT.

"The next step is to determine the precise role these genes play in the process, so we can work towards identifying potential therapeutic targets and develop interventions to prevent and fix misfolding in the brain."

Gray matter consists only of neuronal bodies while white matter is protected by a layer of fat. This study has indicated that gray matter expands faster than white matter as the brain develops, and this instability leads to folding. But there is a pattern, which is the same among members of a species.

Sheep brains fold in the womb like human brains do. In this work, the researchers assessed genetic and structural changes in different parts of the brain in various sections of the folds at different developmental time points.

"Understanding the changes in the cortical plate during brain folding is paramount since this region changes so dramatically during this process," said postdoctoral researcher Dr. Sebastian Quezada Rojas. "We found some genes have higher expression in regions that fold outward and lower expression in regions that fold inwards. Other genes reverse this pattern. Together, these genetic expression patterns might explain why the cortical folding pattern is so consistent between individuals of the same species."

Changes in the number of dendrites formed by the neurons correlated with gene expression differences.

"We believe the regions that fold outward and inward are programmed to behave differently, and the shape of the neurons affects the way these areas fold. Untangling these connections will be focus of the next stage of this research," Quezada Rojas said.

Image credit: Pxfuel

Sources: AAAS/Eurekalert! Via RMIT University, Cerebral Cortex

About the Author
BS
Experienced research scientist and technical expert with authorships on over 30 peer-reviewed publications, traveler to over 70 countries, published photographer and internationally-exhibited painter, volunteer trained in disaster-response, CPR and DV counseling.
You May Also Like
MAY 11, 2022
Drug Discovery & Development
Gene Therapy Shows Promise for Neuropathic Pain
MAY 11, 2022
Gene Therapy Shows Promise for Neuropathic Pain
A gene therapy has been able to inhibit neuropathic pain with no detectable side effects in mice with spinal cord and pe ...
JUN 01, 2022
Health & Medicine
Afraid of New Things? Your Genes Could be Responsible
JUN 01, 2022
Afraid of New Things? Your Genes Could be Responsible
Afraid of New Things? You’re Genes Could be Responsible Scientists have discovered a significant difference in how ...
JUN 05, 2022
Genetics & Genomics
Height & Health - Being Tall Affects Disease Risk
JUN 05, 2022
Height & Health - Being Tall Affects Disease Risk
Height has long been linked to an increase in the risk of disease, but what's been tough to determine is whether thi ...
JUN 12, 2022
Genetics & Genomics
Silent Genetic Mutations Are Not as Quiet as we Thought
JUN 12, 2022
Silent Genetic Mutations Are Not as Quiet as we Thought
Genes hold the recipe for proteins, which are made of amino acids. DNA only has four letters, or nucleotides, and each s ...
JUN 30, 2022
Cardiology
Greenlanders Face Genetic Heart Risks
JUN 30, 2022
Greenlanders Face Genetic Heart Risks
About one third of Greenlanders are at higher risk of heart disease and high cholesterol.
JUL 07, 2022
Cell & Molecular Biology
Mini-Kidneys Reveal New Insights, Treatments for Multiple Disorders
JUL 07, 2022
Mini-Kidneys Reveal New Insights, Treatments for Multiple Disorders
Researchers have been able to use animal models to study human disease, but there are clear limitations to that approach ...
Loading Comments...