Money Matters, Simplified.
Sequencing of body lice genome successful
by Neha Gupta - June 22, 2010 - comments
The body louse is responsible for spreading various human diseases including epidemic typhus, relapsing fever, and trench fever.
Scientists have successfully sequenced the genome of the human body lice, offering insights into the insect evolution which could help us destroy the blood sucking organisms.
Scientifically known as Pediculus humanus humanus, the body louse is closely related to the head louse and has the smallest genome, reveal the multi center team of researchers.
“This likely reflects its somewhat protected habitat and predictable diet,” said University of Illinois entomology professor Barry Pittendrigh.
"The ecology of lice is very, very simple. It either lives in your hair or on your clothing, and it has one type of meal, and that's blood. So most of the genes that are responsible for sensing or responding to the environment are very much reduced," he said in a university news release.
The body louse contains the least detoxification enzymes in any insect, resulting in its resistance towards any insecticide or chemical. Due to this resistance, it evades almost any repellant.
It also has the minimum genes related to light reception, odors and tastes.
Responsible for various human diseases
The body louse is responsible for spreading various human diseases including epidemic typhus, relapsing fever, and trench fever.
It has since history been blamed for spreading typhus and trench fever to Napoleon's retreating army in Russia in 1812.
Due to their complete dependence on humans, the louse would die if kept away from its host for long, claim researchers.
The genome sequencing of the insect would be an important key to understanding the co-evolution of disease-carrying parasites and their bacterial co-conspirators.
"Lice have been used to understand human evolution and migration. They've been used to estimate when we started wearing clothing," Pittendrigh said.
"The genome should also help us develop better methods of controlling both head and body lice."
Consists of 108 million DNA base pairs
When compared with other free ranging relatives, the body louse proves to be biologically and genetically more limited.
Its genome contains just 108 million DNA base pairs, as compared with the more than 3 billion base pairs in the human genome.
Further, Candidatus Riesia pediculicola, a bacterium living symbiotically inside the louse’s guts is responsible for supplying the insect with the essential vitamin pantothenate, B5, which it is unable to synthesize on its own.
The study is published online in the Proceedings of the National Academy of Sciences for the week of June 21-25.