In a paper published in Genome Research on Nov. 4, scientists at the Genome Institute of Singapore (GIS) report that what was previously believed to be "junk" DNA is one of the important ingredients distinguishing humans from other species.

Scientists studying biological systems at the molecular level now have a new hybrid technique to probe the dynamics of the Holliday junction. The Holliday junction is a four-stranded DNA structure that forms during a process known as homologous recombination, which occurs when damaged DNA is repaired. Understanding how DNA repairs itself is an essential step in ultimately developing therapies for genetic disorders.

In the past ten years, researchers in genome stability have observed that many kinds of cancer are associated with areas where human chromosomes break. They have hypothesized – but never proven – that slow or altered replication led to the chromosomes breaking.