Junk DNA is associated with diseases

• April 28, 2024

The international scientific consortium where it participates in an outstanding way Félix Recillas Targa , of the Institute of Cellular Physiology (IFC) of the UNAM, described areas of the genome little studied - called non-coding DNA - that by acting as a "border" helps regulate the expression of different genes in their environment.

Alterations in the also badly named "DNA junk "They are frequently associated with diseases such as multiple sclerosis, as demonstrated in the article published in the latest issue of the prestigious journal Nature Structural & Molecular Biology.

The information contained in these areas is essential for the organization and expression of genes and they are so important that they have remained constant throughout evolution, as discovered by Mexican, Spanish, Portuguese and American researchers.

Recillas Targa explained that the genome is made up of genes and "no genes"; that is, it has about 2% of DNA coding (30 thousand genes) and 98% non-coding, which does not generate a peptide product or protein, although it is also formed by nitrogenous bases -adenine, cytosine, guanine, thymine.

The latter was called "junk DNA" because it was not understood how it worked or had been given the attention it deserves. "It turns out that within those broad regions of the genome, there is a lot of information, such as the elements that regulate the on and off of the genes ”.

For his research, the also head of the Department of Molecular Genetics of the IFC, together with his collaborators, used as "anchor" a protein called CTCF . The objective was to determine, with massive sequencing systems, how it is distributed throughout the genome, in coding and non-coding regions.

In addition, it was proved that the CTCF can "build" chromatin loops (component of the chromosomes), which means that the genome is not linear, but forms rosettes that allow the "approach" and the interaction at a distance between its different elements regulatory

It is thought that the non-coding DNA fails for two reasons: one is the strictly genetic, because there are also mutations in the intergenic regions (loss, gain of chromosomes or even plimorphisms).

The other would be epigenetic defects or at the level of the formation of chromatin loops, responsible for the interactions at a distance between different regions of the genome without being exclusive. "One of the conclusions of this work suggests that in certain pathologies there is a combination of the two causes," he said.

The scientist acknowledged that this investigation does not yet have a direct medical application, and "we are far from that"; It is a high-level basic research work, but if we do more corroborations, tests and tests, maybe it could have a use in the future.

However, now a collaboration with the Institute of Biomedical Research is planned to make an "interface" with the hospital. "We lack the clinical part and we are interested in having it".

Video Medicine: The Noncoding Genome: Finding Treasures in our Junk DNA (April 2024).