Another code within DNA has been discovered by scientists -- a finding that the researchers say sheds light on how changes to DNA affect health.
Since the genetic code was first deciphered in the 1960s, scientists have believed it was used solely to write information about proteins. But this new study from University of Washington scientists found that genomes use the genetic code to write two separate languages.
One language describes how proteins are made, and the other helps direct genetic activity in cells. One language is written on top of the other, which is why this other language went undiscovered for so long, according to the report in the Dec. 13 issue of Science.
"For over 40 years, we have assumed that DNA changes affecting the genetic code solely impact how proteins are made," team leader Dr. John Stamatoyannopoulos, an associate professor of genome sciences and of medicine, said in a university news release.
"Now we know that this basic assumption about reading the human genome missed half of the picture," he said.
This other code may be where diseases can develop, when the more complicated job of regulating how genes are expressed in cells goes awry, the study authors suggested. The finding could have a significant impact on how scientists and doctors interpret a patient's genetic code and lead to new ways to diagnose and treat health problems, the researchers said.
"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," Stamatoyannopoulos explained in the news release.
-- Robert Preidt