Pseudogenes are indeed (sometimes) functional

Pseudogenes are sequences that originate from functional genes, but are not coding for proteins. Originally it was thought that pseudogenes were non-functional and that they were artifacts from the evolutionary history.

But recent developments in science propose another theory that is radically different.

The origen of pseudogenes can be explained by the retrotransposition of functional mRNA that is randomly inserted in the genome. They are similar to functional genes, but lack introns and other characteristics. A second mechanism by which pseudogenes could originate from duplicated genes that have accumulated deleterious mutations and therefore are not functional anymore.
Pseudogenes are abundant in all eukaryotic organism and in in humans 12,000 pseudogenes show evidence of being pseudogenes. A remarkable insight is that 60% of the pseudogenes in humans are also conserved.

..The high abundance and conservation of the pseudogenes in a variety of species indicate that  selective pressures preserve these genetic elements, and suggest that they may indeed perform important biological functions..

Recent evidence has demonstrated that more and more of the pseudogenes are transcribed in various organisms. The authors of the article conclude that:

..that the pseudogene transcripts are in fact functional but not random products. More and more accumulating examples support this alternative explanation..

The overall conclusion of the article is that:

..The study of functional pseudogenes is just at the beginning. There remain many questions to be addressed, such as the regulatory elements controlling the cell or tissue specific expression of pseudogenes. But, definitely, the so-called pseudogenes are really functional, not to be considered any more as just “junk” or “fossil” DNA. Surely, many functional pseudogenes and novel regulatory mechanisms remain to be discovered and explored in diverse organisms…

One of the major implications of this discovery is that the portion of junk DNA in the genome is steadily shrinking. Evolutionary theory says that pseudogenes are random byproducts of evolution in action. But this demonstrates that the portion of the genome that is non-functional is less than expected.

Scientist discover over and over that most of the genome is functional,  that genomic structures are more complex than expected and that non-coding DNA has a remarkable impact on regulation of essential biological functions. To me, it seems therefore more justified to say that this gives more credibility to the concept of a designer.


One thought on “Pseudogenes are indeed (sometimes) functional

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your 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