Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Head and Body Lice Appear to be the Same Species, Genetic Study Finds

10.04.2012
A new study offers compelling genetic evidence that head and body lice are the same species. The finding is of special interest because body lice can transmit deadly bacterial diseases, while head lice do not. The study appears in the journal Insect Molecular Biology.

Scientists have long debated whether human head and body lice are the same or different species. The head louse (Pediculus humanus capitis) is a persistent nuisance, clinging to and laying its eggs in the hair, digging its mouthparts into the scalp and feeding on blood several times a day.

The body louse (Pediculus humanus humanus) tends to be larger than its cranial counterpart, and is a more dangerous parasite. It lays its eggs on clothing, takes bigger blood meals, and can transmit relapsing fever, trench fever and epidemic typhus to its human host.

Previous studies have found that even when they are both present on the same host, head and body lice don’t stray into each other’s territories. They don’t breed with one another in the wild, but they have been shown to successfully reproduce under specific laboratory conditions. The presence of head lice has little to do with human hygiene, but body lice seem to appear out of nowhere when hygiene suffers – in times of war or economic hardship, for example.

In the new study, researchers compared the number and sequences of all of the protein-coding genes expressed at every stage of the head and body louse life cycles.

“We were interested in understanding potentially how closely related head lice and body lice are,” said University of Illinois entomology professor Barry Pittendrigh, who led the study. “Do they have the same number of genes? Do those genes look very similar or are they very different? What we found is that these two organisms are extremely similar in terms of their protein-coding genes.”

The researchers also exposed the lice to a variety of environmental conditions to capture the greatest variety of gene activity.

“My colleagues at the University of Massachusetts, led by veterinary and animal sciences professor John Clark, collected lice at every developmental stage, exposed them to every pesticide they could get their hands on, multiple bacterial challenges, several physical challenges – cold, heat – to get the lice to express as many genes as possible,” Pittendrigh said. Very few differences were detected in the number or sequences of genes they expressed.
“The differences in their sequences were so minor that if we didn’t know they were separate groups, we would have considered them the same species,” he said.

“As body lice transmit diseases and head lice don’t, this system provides a unique opportunity to understand subtle changes that allow body lice to transmit human diseases,” said graduate student Brett Olds, who conducted the genetic analysis.

The study team also included Illinois animal biology professor Kenneth Paige; entomology graduate students Laura Steele and Tolulope Agunbiade; and S.H. Lee, from the department of agricultural biotechnology at Seoul National University. The National Institute of Allergy and Infectious Diseases at the National Institutes of Health supported this research.

Editor’s notes: To reach Barry Pittendrigh, email pittendr@illinois.edu
The paper, “Comparison of the transcriptional profiles of head and body
lice,” is available online

Diana Yates | University of Illinois
Further information:
http://www.illinois.edu

More articles from Studies and Analyses:

nachricht New study: How does Europe become a leading player for software and IT services?
03.04.2017 | Fraunhofer-Institut für System- und Innovationsforschung (ISI)

nachricht Reusable carbon nanotubes could be the water filter of the future, says RIT study
30.03.2017 | Rochester Institute of Technology

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

Bare bones: Making bones transparent

27.04.2017 | Life Sciences

Study offers new theoretical approach to describing non-equilibrium phase transitions

27.04.2017 | Physics and Astronomy

From volcano's slope, NASA instrument looks sky high and to the future

27.04.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>