Rakyan lab publishes BioEssays review on rDNA genetic variation
Schematic representation of the human Ribosomal DNA loci.
In recent years, geneticists have uncovered intricate relationships between variation in the genome and human traits, both in health and disease. Unfortunately, much still remains unexplained, in no small part because some regions of the genome have proven elusive to explore. One of these regions is the Ribosomal DNA — or rDNA, as it is most commonly known. As its name suggests, the rDNA encodes for the Ribosomal RNAs (or rRNAs), which form the functional core of the ribosomes, the protein-making machines of the cells. Its role is thus absolutely essential for life, and, for a long time, this led researchers to believe that no variation could exist in the rDNA within a species.
In humans and many other species, the rDNA appears in hundreds of copies across several chromosomes, making it quite difficult to analyse. In spite of this difficulty, researchers have managed to determine not only that rDNA varies across individuals of a species, both in how many copies in total one harbours and the specific DNA sequence of those copies, but also that not every copy within one individual's genome is identical. Most importantly, recent studies are showing that this variation may influence a variety of traits, and should thus not be ignored in future studies.
In a newly published review in BioEssays, the members of the Rakyan Lab compile what is currently known about rDNA genetic variation and its impact on human traits. The article also suggests how the field can advance in its understanding of the underlying biological mechanisms. As the review shows, the "Dark Side" of the genome is starting to lit, paving the way to fascinating discoveries in human biology.