Mobile DNA Elements Can Disrupt Gene Expression and Cause Biological Variation, Study Shows

According to an article on the website of Science Daily,  a group of researchers at the Ohio State University Comprehensive Cancer Center found that transposons are can affect gene expression even if they are thousands of base pairs away from premature stop site in the genomic DNA. Another factor that determined whether or not the transposons affected the expression of gene was gender of the parent that the transposon was inherited from.

Transposons  are movable pieces of DNA, also called “jumping genes” as they can move from one location to another on a chromosome, but unlike viruses they can’t move from one cell to another. Transposons makeup half of the genomic DNA in humans and mice as they have accumulated in the genome over time.



The transposons studied in this research study were that of diverse mouse strains called endogenous retroviruses (ERVs). They found that ERVs disrupted the gene expression by halting gene transcription. If the gene containing an ERV came from the father it produced an incomplete form of mRNA but if it came from the mother a full length mRNA was produced from the gene.

According to an assistant professor of molecular virology, immunology and medical genetics Dr. David E Symer,  this an unusual example of DNA imprinting.They are in the process of determining how the transposon is able to trigger or halt the expression of the gene and also how the transposons affect the gene expression differently based on the gender of the parent that it came from. Dr. Symer says these finding are important in understanding mechanisms of natural variation and human biology also cancer and other diseases.