Sunday 7 February 2016

New Nail in the Junk DNA Coffin: “Junk” Prevents Breast Cancer


Even in “simple” organisms, non-coding RNA is anything but simple. Image courtesy of David S. Goodsell, RCSB Protein Data Bank, public domain.




Joel Kontinen

Richard Dawkins and some other ardent evolutionists have used junk DNA as an argument for undirected evolution. They have called it the ultimate parasite and vestigial and some still dislike the idea that it could actually have a function.

However, in 2010, the Encyclopedia of DNA Elements (ENCODE) project disclosed that most of what was thought to be junk or useless leftovers from Darwinian evolution actually had beneficial consequences for us. In other words, junk DNA or, as it usually defined, “the strand of DNA that does not carry the information necessary to make proteins,” is anything but junk.

We keep on getting to know of more ways of how this assumed evolutionary junk is actually very necessary for us and for other living creatures as well.

The latest instalment comes from cancer research. A study conducted in the Universities of Bath and Cambridge, UK, found that this assumed junk “plays a role in suppressing cancer.”

A press released issued by the University of Bath states:

In recent years it has become apparent that a lot of this non-coding DNA is actually transcribed into non-coding RNA…

Now a team of scientists from Bath, Cambridge and the USA has identified a piece of non-coding RNA – transcribed from a stretch of DNA that doesn’t code for a protein – that stops cells turning cancerous.

The researchers hope their discovery, published in Nature Communications, will help develop new treatments for cancer
.”

Cancer can be caused by switches that determine which cells should replicate and which should die off. Sometimes the switch gets stuck in the on position, leading to a spread of cancer.

Dr Lovorka Stojic, who works at the Cancer Research UK Cambridge Institute, discovered that a strand of non-coding RNA known as GNG12-AS1 “prevents the growth switch getting stuck and suppresses metastasis. The specific genomic region where this non-coding RNA is located often gets damaged in breast cancer patients – this control is removed and the cancer cells spread.”

The role of non-coding RNA is more complicated than this. To keep cells healthy, it employs two mechanisms: 1) “regulating the levels of DIRAS3, one of its neighbouring genes that is involved in cell replication” and 2) “suppressing a network of genes that prepare cells to change their shape and prepare for metastasis.”

To sum up: non-coding RNA does not sound at all like junk. It prevents cancer from spreading.

It appears to be a very intelligent solution.

Source:

University of Bath. 2016. 'Junk' DNA plays role in preventing breast cancer. (February).