Scientists have sequenced the entire genome of the common housefly and say their findings should help uncover new cures for human diseases.
The fly can carry some 100 illnesses, including one that can blind. By comparing its DNA with that of a fruit fly, the US team at Cornell University pinpointed the genes that makes houseflies immune to the pathogens they harbour. They also found unique code that helps the fly dissolve waste, such as faeces.
Information about these genes could help us to handle human waste and improve the environment, Dr Jeff Scott and colleagues told the journal Genome Biology.
Houseflies are ideally suited to spreading disease. They have regular contact with carcasses, rubbish and other septic matter containing bacteria, viruses and other “nasties” such as tapeworms.
They enjoy some of the same food that we do, and because they are very good at evading our detection, they get plenty of opportunities to land on it (as well as on us).
It is believed that they carry so many pathogens because they feed on liquid or semi-liquid matter – often faeces. Their constant food intake, in turn, means that they need to evacuate large amounts of faeces – along with any pathogens they are carrying – whenever they land for more than a few seconds.
Unlike us, they don’t get sick from this dirty lifestyle.Dr Scott and his team were intrigued to find out why and to see if it might be possible to utilise this skill for mankind’s benefit.