Junk DNA finds its purpose

Junk DNA finds its purpose

Scientists finally discover junk DNA has a purpose… and it may positively affect future treatment of genetic disease.

JUNK DNA: “I don’t know how to put this but I’m kind of a big deal.” #sciencebreakthrough #ronburgundy

The British Science Festival is always an enlightening place to visit. It has a special place in my heart because the festival made me want to work in science, and so was probably the biggest single influencer on my career choice.

At this year’s festival Sir Paul Nurse, professor extraordinaire, President of the Royal Society and head of many other prestigious organisations spoke about some new scientific research. He was careful not to overstate it, as it is so easy for people to misinterpret a single scientific discovery as ‘world-changing’ rather than a step along the path of progress. An international consortium, led by the Sanger Institute (Cambridge) here in the UK, working on a project called Encode has been working on the analysis of the human genome.

For the last 10 years all biology students have learned that only 2% of DNA in the genome codes for protein. The rest was termed ‘junk DNA’. No-one knew what it was for, only that it didn’t code for protein, and therefore had no function that we knew of. Encode have now managed to make sense of these regions, discovering sequences that do not code protein, but which make ‘micro-RNA’ with many different functions. Some are active as markers and some help with signalling. Some may be a switch, meaning that the DNA that codes for protein is more likely to be used. It has certainly opened up new possibilities.

While it was always clear that 98% of the genome could not be ‘junk’ since it clearly had a function, science is evidence-based, and before this work there was no evidence to show the purpose of these regions. What this work provides is a wide range of possibilities. It shows there is more to DNA than producing protein, and gives an idea of how we can tell whether a gene will be activated.

This may be important when looking for genetic disease markers. People may have the genes for a genetic disease, but not develop it. Perhaps the junk DNA could give a clue as to why? It could also tell us more about how the environment influences our genes, and so what happens in our lives can influence the biological make-up of our children.

While this discovery may not change science in a single bound, it has opened up our understanding of genetics and paved the way for many further discoveries.