There is a second hidden code stowed away in our DNA, genome scientists
have recently discovered. This secondary code stores information that affects the way the DNA instructions are read. This may help molecular geneticists understand how mutations are a factor in the diagnosis and treatment of certain diseases.
Dr. John Stamatoyannopoulos, An associate professor of genome sciences and medicine at the University of Washington, is credited with this discovery. These findings were received for publication on 19 July 2013, accepted for publication 23 October 2013, and finally published in the 13 December 2013 edition of Science. A DNA research project called ENCODE conducted the research. The group has been tasked with finding out how the human genome encodes biological functions.
It has been know for a long time that DNA is the source for the instructions on how to build proteins, but now the University of Washington researchers have found that the genetic code is written in two distinct languages. The first is the one that scientists have been familiar with and have focused most of their efforts on thus far. It is the language for constructing proteins molecule-by-molecule, by specifying the order in which to build the amino acids. The other language seems to be superimposed on the first, providing additional instructions. These are called the “transcription factor recognition sequences.”
This second language has eluded scientists for over 40 years because of the way the two overlap and have a complex system of interplay. Now that a hidden code in the genome has been discovered by researchers, more of the picture is complete. If the first function is seen as broad strokes on a canvas, the second function is the subtle accents. Although the Human Genome Project has completely mapped the human genome in 2003, there is still a long way to go in understanding how any of it works.
The scientists at the University of Washington have found that some codons in the DNA have two separate meanings, and they have called these duons. Duons have one function that works to encode protein sequences, and also another for gene control, acting as a stabilizing factor.
DNA has all the genetic information needed for an organism to live, grow, and reproduce. DNA is a polymer made out of a long string of nucleotide base pairs. It is not a single molecule, but rather two separate molecules that adhere to each other, intertwining in the famous double helix structure. In a process called transcription, DNA is used to create strands of RNA, which specify the exact sequence to build a protein. DNA uses a code of 64 different codons, which act like an alphabet.
The discovery of the two-fold hidden code of duons will likely have ramifications in pathology; the simultaneous action of both mechanisms will have to be explored in tandem. Genome researchers have a long ways to go in unraveling the mysteries of DNA.
By K. Elsner