The return of Retrovirus buried in human DNA


A team of scientists at the University of Oxford has discovered that a protein called Hemo, made by a fetus and the placenta, is produced from viral DNA that entered our ancestors’ genomes 100 million years ago. This protein that courses through the veins of pregnant women, may reawaken retrovirus that contributes to diseases like multiple sclerosis, diabetes, and schizophrenia.

Crux of the Matter

There is a Retro Version of a Virus too?
A retrovirus (RV) invades a host cell and inserts its genes into that cell’s DNA. These viral genes co-opt the cell’s machinery, using it to make new viruses that escape to infect more cells. If a retrovirus happens to infect an egg or sperm, its DNA can potentially be passed to the next generation and the generation after that. They can force cells to make copies of their DNA, which are inserted back in the cell’s own genome.

What do the Virologists Know About it?
Aris Katzourakis, a virologist at the University of Oxford, and his colleagues recently published a commentary in the journal Trends in Microbiology in which they explored the possibility of viral genes affecting our health in a variety of unexpected ways. In January, Dr. Katzourakis was a co-author on a study showing that one retrovirus common in mammals also is present in fish like cod and tuna.

A team of French researchers engineered healthy human cells to make a viral protein found in many tumors and watched the cells grow in a petri dish. They changed shape, as cancer cells do, becoming long and skinny. And they also started to move across the dish.

Can These Ancient Genomes be Used for a Good Cause?
Researchers have added that some of the RVs become endogenous retroviruses that provide an innate immune response, which is the body’s first line of defense against pathogens. They can fight off infections including viruses and bacteria. A genome-editing technique was used to remove an ERV sequence that was found close to an immunity gene. The team will next investigate whether endogenous retroviruses play a similar role in the immune systems of other animals


DNA or deoxyribonucleic acid is a long molecule that contains our unique genetic code. Like a recipe book, it holds the instructions for making all the proteins in our bodies. DNA contains four basic building blocks or ‘bases’: adenine (A), cytosine (C), guanine (G) and thymine (T). The order, or sequence, of these bases form the instructions in the genome. Being a two-stranded molecule, it has a unique ‘double helix’ shape, like a twisted ladder. The human genome is made of 3.2 billion bases of DNA but other organisms have different genome sizes. It was first discovered by Francis Crick and James Watson with the help of Rosalind Franklin and Maurice Wilkins. More Info