Researchers have discovered that “junk” DNA from ancient viruses can play a crucial role in controlling genes, particularly during early development. The study found that nearly half of the human genome consists of segments called transposable elements (TEs), which are remnants of ancient viruses that embedded themselves in our ancestors’ genomes millions of years ago.
For decades, scientists believed TEs were useless and served no purpose. However, new evidence suggests they may be essential in regulating gene expression. The study focused on a specific family of TEs called MER11, which belongs to a larger class of TEs that entered primate genomes 40 million years ago.
The researchers inserted nearly 7,000 of these TE sequences into cells and measured the resulting effects. They found that the youngest members of the MER11 family had a strong ability to activate genes, with unique “transcription factor binding sites” that regulate gene expression.
Subtle variations in these sequences existed between humans, chimpanzees, and macaques, which affected their regulatory effect. The study’s findings highlight the importance of further research into the genome sequence, particularly for understanding virus-like transposon repeats.
This discovery opens up new avenues for investigation, including using CRISPR to delete parts of TEs and unravel their roles in regulating gene expression in both health and disease.
Source: https://www.livescience.com/health/genetics/ancient-viruses-embedded-in-our-dna-help-switch-genes-on-and-off-study-finds