Tough Antarctic Fly has its Genome Mapped

Researchers have sequenced the genome of the Antarctic midge.

The Antarctic midge (Belgica antarctica) is the only known animal endemic to the cold, barren Antarctica. The insect has no wings and researchers have now found that it has a tiny genome that probably helps it survive the icy continent.

Washington State University scientists and their colleagues sequenced the genome of the fly.

The fly is so tough that its larvae develop over not one, but two Antarctic winters. The insect survives the cold, chilly winds, salt and relentless UV radiation. Adult midges live for only a week or so.

The WSU researchers believe that the tiny genome helps the fly cope with the harsh Antarctic winters.

"It's tiny," said Joanna Kelley, a Washington State University assistant professor who recently sequenced and analyzed the genome with colleagues around the U.S. "That was a huge surprise. I was very impressed."

The fly has just 99 million base pairs compared to 3.2 billion base pairs found in human genome. Most of the genes in the fly genome are dedicated to regulation and developmental processes, while few genes are associated with odor detection. The study is published in the journal Nature Communications.

The researchers say that the fly doesn't need several odorants as it doesn't fly and so, doesn't rely on its sense of smell for foraging.

The team found it rather surprising that the midge fly has incredibly short genome with fewer repeated base pairs.

"We suspect that it's somehow an adaptation to the extreme environment," Kelley said in a news release. "And it opens up a lot of interesting hypotheses to hopefully test by sequencing additional Antarctic organisms or sub-Antarctic organisms, because there are other flies, or Diptera, on some of the sub-Antarctic islands. We're really interested to see whether or not they have similar genomes."

The study was funded by National Institutes of Health National Research Service Award.