Non-coding regions play an important role in maintaining an organism’s genetic integrity, according to Peter Andolfatto, an assistant professor of biology at UCSD, in the October 20 issue of Nature.

“Sequencing of the complete genome in humans, fruit flies, nematodes and plants has revealed that the number of protein-coding genes is much more similar among these species than expected,” he says. “Curiously, the largest differences between major species groups appear to be the amount of ‘junk’ DNA rather than the number of genes.”

Andolfatto also found that “junk” regions exhibit an unusually large amount of functional genetic divergence between different species of Drosophila, further evidence that these regions are evolutionarily important to organisms. This implies that, like evolutionary changes to proteins, changes to these “junk” parts of the genome also play an important role in the evolution of new species.

Source: University of California, San Diego news release