Subscribe to the BioNews newsletter for free

Login
Advanced Search

Search for
BioNews

Like the Progress Educational Trust on Facebook


The Fertility Show


 

Global study counters 'junk' DNA theory

10 September 2012

By Emma Stoye

Appeared in BioNews 672

Scientists have found that 80 percent of DNA in the human genome, previously thought to be of no use, have important functions. This discovery dismantles the 'junk' DNA theory after years of uncertainty.

The revelation was published last week as part of the most comprehensive analysis of the human genome to date. The project, known as the Encyclopedia of DNA Elements (Encode) involved over 400 scientists at 32 institutions worldwide.

The nickname 'junk' DNA was coined many years ago to describe the DNA present in many genomes that doesn't code for proteins, and therefore did not appear to serve any clear function. The completion of the Human Genome Project a decade ago revealed that only 2 percent of human DNA coded for proteins, while the rest appeared to have no purpose. Encode was launched in 2003 to further investigate the genome.

Now, after almost ten years, researchers have arrived at the conclusion that the majority of non-coding DNA actually plays a pivotal role in keeping the body running. These stretches of DNA act as regulatory switches that control whether certain genes are switched on or off in specific cells.

'We always knew that protein-coding genes were not the whole story', Dr Ewan Birney from the European Bioinformatics Institute, who led the project, told Wired. 'A much bigger part of the genome - a surprising amount, in fact - is involved in controlling when and where proteins are produced, than in simply manufacturing the building blocks'.

The team found over four million switches among the 98 percent of non-coding DNA formerly thought to be 'junk'. Many of these are located in completely different areas of the genome to the genes they control, which is perhaps why, until now, they remained undetected.

The findings could open up a new chapter in medical research, according to Professor Mike Stratton, director of the Wellcome Trust Sanger Institute. 'The Encode project will change the way many researchers conduct their science and give those who seek to understand disease a much better grasp of where genetic variation can affect our genome for ill'.

Dr Birney adds: 'Many of the switches we have identified are linked to changes in risk for conditions from heart disease to diabetes or mental illness. This will give researchers a whole new world to explore and ultimately, it's hoped, will lead to new treatments'.

It may, however, be some time before patients start to benefit from these new insights, as scientists must first detangle the complex pathways that exist within the newly discovered genetic control panel.

RELATED ARTICLES FROM THE BIONEWS ARCHIVE

24 July 2017 - by Ipsita Herlekar 
Almost 75 percent of the human genome is 'junk DNA', suggests a new study...
23 March 2015 - by Dr Barbara Kramarz 
The human genome contains genes from plants, fungi and various microorganisms that cohabited with our ancestors, research shows...
04 August 2014 - by Chris Baldacci 
Researchers at the University of Oxford have estimated that only 8.2 percent of human DNA has been left unchanged as the species has evolved and is therefore likely to be functional...
24 June 2013 - by Dr James Heather 
Big data, open science, and DNA a-go-go; last week's broadcast of The Life Scientific looked to have it all...
17 December 2012 - by Simon Hazelwood-Smith 
Genetic mutations are not the only contributing factor in the growth of cancerous tumours, say scientists...

28 August 2012 - by Holly Rogers 
An outbreak of a drug-resistant bacterial bug, which killed six people and infected 11 more, was stopped partially thanks to genome sequencing, a paper in Science Translational Medicine reports...
23 July 2012 - by Dr Kimberley Bryon-Dodd 
The genetic mutations underlying colon and rectal cancer are so similar that these cancers should be classified as one disease, a study suggests. Researchers analysed over 200 tumour samples and also identified genes that could serve as targets for future drug treatments...
16 July 2012 - by Daryl Ramai 
Technology that relies on less DNA to more accurately sequence people's genomes has been unveiled by a US biotech company...
11 June 2012 - by Dr Daniel Grimes 
Researchers have sequenced the entire genome of an 18 and a half-week-old fetus using DNA samples from the blood of its mother and saliva samples from its father. These findings provide a proof of principle that a fetus can be examined for genetic defects using non-invasive technologies...
06 June 2012 - by Dr Victoria Burchell 
A wealth of whole genome data – or the entire genetic codes – from children with cancer has been released by scientists in the US. The researchers claim the database more than doubles the volume of highly detailed, whole genome data available worldwide...

HAVE YOUR SAY
Be the first to have your say.

You need to or  to add comments.

By posting a comment you agree to abide by the BioNews terms and conditions


- click here to enquire about using this story.

Published by the Progress Educational Trust

CROSSING FRONTIERS

Moving the Boundaries of Human Reproduction

Public Conference
London
8 December 2017

Speakers include

Professor Azim Surani

Professor Magdalena Zernicka-Goetz

Professor Robin Lovell-Badge

Sally Cheshire

Professor Guido Pennings

Katherine Littler

Professor Allan Pacey

Dr Sue Avery

Professor Richard Anderson

Dr Elizabeth Garner

Dr Jacques Cohen

Dr Anna Smajdor

Dr Andy Greenfield

Vivienne Parry

Dr Helen O'Neill

Dr César Palacios-González

Philippa Taylor

Fiona Fox

Sarah Norcross


BOOK HERE

Good Fundraising Code

Become a Friend of PET HERE and give the Progress Educational Trust a regular donation