Australasian Science: Australia's authority on science since 1938

What’s Jumped Into Your DNA?

Credit: k_e_n/Adobe

Credit: k_e_n/Adobe

By Atma Ivancevic

DNA elements that can transfer between species make up an astonishing 17% of the human genome, and have been associated with schizophrenia and cancer.

The full text of this article can be purchased from Informit.

A tick is on the hunt for prey. It spots a resting snake: it’s first victim. The tick feeds hungrily, sucking in blood and DNA. Later, it spots another delicacy in the form of grazing cattle. The tick hops from animal to animal, latching on tightly to consume a second blood meal. The cow squirms uncomfortably at the sudden intrusion, but quickly forgets and goes back to grazing.

Unbeknown to all, the tick has just transferred DNA from the snake to the cow. This process is called horizontal transfer, and the DNA is a transposable element.

Transposable elements are mobile DNA sequences. Unlike genes, they have no known function but they do have the ability to copy and paste themselves to new locations within the genome.

Sometimes these elements can jump into new organisms by hitching a ride on parasites such as ticks. Transferred elements can then start replicating inside the new host, bloating out the genome and interrupting genes.

If they get into reproductive cells like eggs and sperm, they can be passed on to the next generation. Sometimes this leads to the evolution of new species traits. Other times it can lead to disease.

In new research published in Genome Biology (, we looked at two transposable elements: BovB and L1....

The full text of this article can be purchased from Informit.