UW Health Sciences & UW Medicine
Posted under: Health and Medicine, News Releases,
Research, Science, Technology
Scientists have discovered a second
code hiding within DNA. This second code contains information that changes how
scientists read the instructions contained in DNA and interpret mutations to
make sense of health and disease.
Genome scientist Dr. John
Stamatoyannopoulos led a team that discovered a second code hidden in DNA.
A research team led by Dr. John
Stamatoyannopoulos, University of Washington associate professor of genome
sciences and of medicine, made the discovery. The findings are reported in the
Dec. 13 issue of Science.
Read the research paper. Also see commentary in Science, “The
Hidden Codes that Shape Protein Evolution.”
The work is part of the Encyclopedia
of DNA Elements Project, also known as ENCODE. The National Human Genome
Research Institute funded the multi-year, international effort. ENCODE aims to
discover where and how the directions for biological functions are stored in
the human genome.
Since the genetic code was
deciphered in the 1960s, scientists have assumed that it was used exclusively
to write information about proteins. UW scientists were stunned to discover
that genomes use the genetic code to write two separate languages. One
describes how proteins are made, and the other instructs the cell on how genes
are controlled. One language is written on top of the other, which is why the
second language remained hidden for so long.
“For over 40 years we have assumed
that DNA changes affecting the genetic code solely impact how proteins are made,”
said Stamatoyannopoulos. “Now we know that this basic assumption about reading
the human genome missed half of the picture. These new findings highlight that
DNA is an incredibly powerful information storage device, which nature has
fully exploited in unexpected ways.”
The genetic code uses a 64-letter
alphabet called codons. The UW team discovered that some codons, which they
called duons, can have two meanings, one related to protein sequence, and one
related to gene control. These two meanings seem to have evolved in concert
with each other. The gene control instructions appear to help stabilize certain
beneficial features of proteins and how they are made.
The discovery of duons has major
implications for how scientists and physicians interpret a patient’s genome and
will open new doors to the diagnosis and treatment of disease.
“The fact that the genetic code can
simultaneously write two kinds of information means that many DNA changes that
appear to alter protein sequences may actually cause disease by disrupting gene
control programs or even both mechanisms simultaneously,” said
Stamatoyannopoulos.
Grants from the National Institutes
of Health U54HG004592, U54HG007010, and UO1E51156 and National Institute of
Diabetes and Digestive and Kidney Diseases FDK095678A funded the research.
In addition to Stamatoyannopoulos,
the research team included Andrew B. Stergachis, Eric Haugen, Anthony Shafer,
Wenqing Fu, Benjamin Vernot, Alex Reynolds, and Joshua M. Akey, all from the UW
Department of Genome Sciences, Anthony Raubitschek of the UW Department of
Immunology and Benaroya Research Institute, Steven Ziegler of Benaroya Research
Institute, and Emily M. LeProust, formerly of Agilent Technologists and now
with Twist Bioscience.
Posted by:
Rajni Jaiswal
Faculty.
