Viruses, Our Unexpected Ancestors

A virus is seen as a lifeless invader, hijacking the body’s cells in order to multiply itself. In most introductory Biology classes, this is the image that viruses are presented as. For most that’s all they end up knowing. The article “Darwin’s Surprise” presented a much more complex view. Viruses play a much more integral role to our evolution than previously thought. More specifically it is retroviruses that integrate their own DNA into that of their hosts and in doing so, they permanently leave their DNA in that cell. When looking into the human genome, certain sections stood out as belonging to retroviruses. This discovery is an amazing addition to the history of human development. For someone like Darwin, this would have been an astonishing discovery. Darwin had made his conclusions based on simple observations. He never had the tools to dig deep and see the microorganisms that make up living tissues. It’s mind blowing how far today’s scientific community has taken Darwin’s original ideas and went beyond just proving it with genomic sequences but also using those same genomic sequences to find the most unlikeliest of connections.

The most unexpected in this article was the way that this new data is being applied for H.I.V. research. H.I.V. has become a large issue in today’s society but at the same time, our closer relatives, the apes, don’t seem to be as impacted by the devastating consequences of the H.I.V. virus. Scientist have now discovered that the reason for this occurrence is due to retroviruses. Humans don’t seem to have a certain retrovirus called PtERV. Apes, on the other hand, have many copies of this virus throughout their genetic code. This discovery has brought H.I.V. research further but as most science solutions do, more questions have arisen from this discovery.

The main point of this article revolves around the possibility of viruses playing a much larger role in the evolution in humans. Retroviruses that have implanted themselves into host cells can pass down their genetic code through the cell division cycles. Some viruses are able to add themselves to gametes, which may result in that virus’s code being sustained through multiple generations. This code is normally read as noncoding DNA but in some cases, it could result in a genetic mutation. It is believed that this is how mammals gained their characteristic live birthing. The article states that development in the mother’s womb is an adaption that was passed on by a retrovirus as both share a similar process, both going through cell fusion. This makes viruses seem almost benign in a way but like mutations, viruses can be positive or negative and at the same time, both viruses and mutations are necessary to keep balance in the world.

The article also posed an interesting topic for discussion: whether these endogenous retroviruses should be revived for testing. I personally am a little against this as only those that can be used for testing out specific ideas should be brought back but to a very limited amount. For example the PtERVs hold much potential to advance H.I.V. research but at the same time people cured of H.I.V. may lose immunity to PtERVs as a result so the revived PtERVs revived for experiments should be carefully handled and disposed.

As a final thought, endogenous retroviruses are like reminders of the past. They represent past encounters that resulted in a battle that ended up fossilizing the virus into the genetic code of humans. These viruses rest dormant within us as remnants. The possibilities for solutions and cures can stretch vast and I’m excited to see where this new development will end up.

Advertisements
This entry was posted in AP Biology, Evolution, Viruses. Bookmark the permalink.

Leave a Reply

Please log in using one of these methods to post your comment:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s