The lack of particular genes in the BEC / TCEAL cluster could be the result in alternations from the autism spectrum, according to a preclinical study recently posted in the journal Genome Biology, led by Professor Jordi Garcia Fernandez of the Faculty of Biology and the Institute of Biomedicine of the University of Barcelona, and researcher Jaime Carvajal, of the University Pablo de Olavide.
The researchers studied transposon-derived genes present in neural complex functions that haven’t yet been reviewed within the autism spectrum disorder and other similar neurological diseases.
The study was carried out on various animal models. It describes some molecular mechanisms crucial in the development of the neocortex in humans and some other placental mammals.
The BEX/TCEAL cluster is a 14-gene family that isn’t understood entirely yet, located in the X chromosome. The genic family’s task is to code small proteins from the hub ones that connect with others, altering their configuration under the local molecular context.
The researchers discovered that the genic group BEX/TCEAL produced from molecular transposon domestication, by which genetic mobile elements can get relocated to other areas of a genome.
During the process, a non-functional transposon gene can take the role of an active element of the genome, which results in a similar development to the other genes.
Transposons are known as a source of evolutionary innovation and adaptation in humans.
Professor Jordi Garcia-Fernandez, leader of the Research Group on Evolution And Development (also known as Evo-Devo), said:
“These are genetic components that have no function or are harmful to the host genome. However, in the case of the BEX/TCEAL cluster, they were domesticated by the molecular machinery of placental mammals’ ancestors. That is, they became new genes.”
Somewhere along the evolutionary process, transposons can somehow lose their capacity to hop “due to new mutations, which join the neighboring effects of the regulator regions where they are, and transform these mobile elements into new genes that have not appeared before during the evolution,” according to researcher Enrique Navas-Perez, the article’s first author.
Researcher Jaime J. Carvajal, the vice-rector of CABD and head of the Research Group on Molecular Embryology, says that such events could be significant when setting unique mammals’ unique traits. He also explained how they analyzed the function of a series of genes that might have contributed to the formation of some brain properties of placental mammals.
Relation To Autism Spectrum Disorders
The study claims that the BEX3 gene, an element found in the BEX/TCEAL cluster, has a significant implication in the m-TOR path, a metabolic path responsible for proliferation and differentiation in a considerable amount of tissues, and especially those of the nervous system.
Other studies suggest that other genes from the cluster are related to neurotrophins and p75, a receptor with a role in neuronal deaths.
The study concluded that the BEX3 gene and likely other parts of the BEX/TCEA complex might have a role in several areas of the autism spectrum disorder and other neurological problems.
Therefore, the mice lacking one of those genes manifested shifts in behavior specific to autism spectrum disorder, aside from presenting typical anatomical and skeletal changes.
“Mice without the BEX3 gene are antisocial and do not interact with other mice,” said researcher Angel Carrion of the UPO’s Department of Neurosciences.