Just one gyrus – not from the cap, but because of a "defective" gene
The gene responsible for the formation of the cerebral cortex has been identified
Kirill Stasevich, Compulenta
A mutation in the gene of one of the proteins of the cell membrane leads to the absence of folds and convolutions in the cerebral cortex, which indicates the underdevelopment of the brain and is expressed in the inferiority of many functions of higher nervous activity.
Replacing just two letters out of three billion in the human genetic code can make a complete idiot out of a genius, scientists from the Yale University School of Medicine (USA) say in an article published in the journal Nature Genetics (Recessive LAMC3 mutations cause malformations of occipital cortical development). No, we are not talking about another "gene of genius" or "gene of mathematical abilities". Scientists have found a gene in which a mutation leads "only" to a violation of the formation of the cerebral cortex – or rather, to a violation of the formation of convolutions in the cortex.
It is believed that a person is so smart due to a special way of laying the neocortex: the cortex of the large hemispheres is covered with numerous folds and convolutions. They increase the surface of the brain without a corresponding increase in the volume of the skull, and thanks to this "excess of brains" in the literal sense of the word, we humans demonstrate highly developed higher nervous activity. By the way, animals with large brains, in particular primates and dolphins, differ in a similar "folding", but in rodents the brain surface has no outstanding irregularities. In general, a person has the most "folded" neocortex.
The researchers studied the genome of a patient whose brain did not have folds in the area responsible for memory, attention, language and thinking abilities and conscious perception. As it turned out, he had a defect in the laminin gamma 3 (LAMC3) gene, one of the most important proteins of cell membranes, on which the formation and structure of intercellular contacts and the attachment of cells to each other depend. Similar genetic defects in two nucleotides, with slight variations, were found in other patients with similar mental problems.
On the left is the brain of a person with a mutation in the LAMC3 gene, on the right is a normal brain.
The zone in which the underdevelopment of the cortex is noted is circled in red.
Illustration by the authors of the study.
Despite the importance of the issue, there have been no assumptions about how the folded structure of the cerebral cortex is formed, so the work in question is, in fact, pioneering. Most likely, the LAMC3 gene plays the role of one of the key regulators of this process, although, of course, dozens (if not hundreds) of other genes may be involved in the formation of the cortex. According to scientists, LAMC3 is also found in other animals – for example, in mice, but in the course of evolution, this gene could acquire new functions critical for brain maturation in higher mammals.
Prepared based on FoxNews: Idiot or Genius? Difference May Come Down to a Single Gene, Scientists Say.
Portal "Eternal youth" http://vechnayamolodost.ru19.05.2011