Biologists have long debated the purpose of non-coding genome regions, but a new study sheds light on their significance. Researchers discovered that one type of transposable element, a viral DNA insert, plays a vital role in regulating cellular function.
Transposable elements (TEs), often referred to as “junk” DNA, are a significant portion of the non-coding genome. Originating from viral infections, TEs have been present in genomes for millions of years and can manipulate gene expression by duplicating within the host genome. A study focused on the MER11 gene found that variations in this gene, grouped according to evolutionary conservation, predicted its regulatory capabilities.
The researchers identified four generations of MER11 variants, with newer versions exhibiting stronger regulatory effects. This suggests that evolution has refined the function of MER11 since a virus introduced it into the human genome. The study proposes that the gain of function in MER genes could be linked to speciation, where small changes can significantly differentiate genomes.
While not all traditionally “junk” DNA is functional, this study highlights the diversity of potential functions within non-coding regions. It’s increasingly reasonable to assume that any stretch of DNA with no apparent function may indeed have a role – we just need to discover it yet.
Source: https://www.extremetech.com/science/researchers-identify-vital-new-role-for-junk-dna