Housefly Could Improve Human Health

The pesky house fly may be annoying, but this buzzing insect's genome could improve human health, according to a new study.

The house fly (Musca domestica) can carry over 100 human diseases, including typhoid, tuberculosis and worms. Fly transmitted trachoma alone causes six million cases of childhood blindness each year.

As the housefly is so involved in human processes, studying its genome will have great implications for human health. By comparing its DNA with that of a fruit fly, a global team of scientists pinpointed the genes that make houseflies immune to the pathogens they harbor, potentially helping scientists create vaccines for a wide range of diseases around the world.

Houseflies are ideally suited to spreading disease, as they regularly come into contact with bacteria and viruses on things such as feces, carcasses, and trash. And unlike humans, flies are not affected by this dirty lifestyle.

"House flies are a fascinating insect for scientists in many areas, such as developmental biology, sex determination, immunity, toxicology and physiology. The completed genome will be a phenomenal tool for researchers in all of these fields and will facilitate rapid advancements," Jeff Scott of Cornell University, the study's lead author, said in a press release.

To unlock the fly's potential as a life-saver, scientists decided to sequence the genomes of six female houseflies, creating a 691 Mb long sequence. They compared it to the 123 Mb genome of the fruit fly, Drosophila melanogastergenome, in order to determine which specific genes were unique to the house fly, and could be candidates for further study.

According to the results, published in the journal Genome Biology, the housefly had many more immune genes than the fruit fly. Its immune genes were also more diverse - presumably to offer it protection against the numerous pathogens it carries.

And if these genes can protect the fly to the many diseases it comes into contact with, then it might have the potential to do the same for humans.

"Although we often think of houseflies as just a nuisance, they can transmit many pathogenic bacteria to people and contribute significantly to disease in poor communities where sanitation is limited," Professor David Conway of the London School of Hygiene & Tropical Medicine told BBC News.

"Many other flies transmit important human diseases and hopefully this work will encourage further genome analyses of these disease vectors, and comparisons between them."