More Uses for "Junk" DNA

A few weeks ago, I posted about how a team of researchers found a new function for junk DNA in encoding instructions for limb development. Another paper appearing in the latest issue of Genome Research theorizes that this DNA is involved in what makes us distinctly human.

From the ScienceDaily article:

"More than 50 percent of human DNA has been referred to as "junk" because it consists of copies of nearly identical sequences. A major source of these repeats is internal viruses that have inserted themselves throughout the genome at various times during mammalian evolution.

Using the latest sequencing technologies, GIS researchers showed that many transcription factors, the master proteins that control the expression of other genes, bind specific repeat elements. The researchers showed that from 18 to 33% of the binding sites of five key transcription factors with important roles in cancer and stem cell biology are embedded in distinctive repeat families.

Over evolutionary time, these repeats were dispersed within different species, creating new regulatory sites throughout these genomes. Thus, the set of genes controlled by these transcription factors is likely to significantly differ from species to species and may be a major driver for evolution."

Read the full article here.

Read the research article in Genome Research here.

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