The following is an edited excerpt.
We have about 20,000 protein-coding genes. If you tally up the amount of DNA they constitute, you get less than 3 percent of the human genome. Which naturally raises the question of what’s in the other 97 percent.
While the basics of the human genome have been clear for decades, the particulars have remained murky. There’s no getting around the hard work of old-fashioned biology–of peering into cells to see what’s going on. And when scientists look in there, things get contentious.
Read the full story here: Listening to the Genome: Music or Noise?
Additional Resources:
- “Reading DNA, backward and forward,” MIT News
In a study published in the journal Nature on June 23, MIT researchers described how cells start and stop copying of RNA in the upstream, or non-protein-coding direction. This may help account for the seemingly purposeless short strands of RNA that researchers have been finding lately. - “Can Cancer Cells Solve the Puzzle of Junk DNA?,” Wall Street Journal
Researchers have taken all kinds of tactics in the attempt to assess the nature of “junk DNA,” including studying the genes found in cancer cells. - “Do humans need mystery ‘junk’ DNA? This carnivorous plant doesn’t,” Los Angeles Times
Ninety-seven percent of human DNA is mysterious, and potentially without purpose. But the inverse is true of the bladderwort–it only has about three percent “junk DNA.”
- “Bits of Mystery DNA, Far From ‘Junk,’ Play Crucial Role,” New York Times
How much of ‘junk DNA” is really gene switches?