Navigation Links
Researchers at LSTM crack the genetic secret of mosquito resistance to DDT and ITNs
Date:2/24/2014

Researchers from LSTM have found that a single genetic mutation causes resistance to DDT and pyrethroids (an insecticide class used in mosquito nets). With the continuing rise of resistance the research, published in the journal Genome Biology, is key as scientists say that this knowledge could help improve malaria control strategies.

The researchers, led by Dr Charles Wondji, used a wide range of methods to narrow down how the resistance works, finding a single mutation in the GSTe2 gene, which makes insects break down DDT so it's no longer toxic. They have also shown that this gene makes insects resistant to pyrethroids raising the concern that GSTe2 gene could protect mosquitoes against the major insecticides used in public health.

Mosquitoes (Anopheles funestus) are vectors of malaria, and most strategies for combating the spread of the disease focus on control of mosquito populations using insecticides. The spread of resistance genes could hold back efforts to prevent the disease. The authors say that knowing how resistance works will help to develop tests, and stop these genes from spreading amongst mosquito populations.

Charles Wondji said: 'We found a population of mosquitoes fully resistant to DDT (no mortality when they were treated with DDT) but also to pyrethroids. So we wanted to elucidate the molecular basis of that resistance in the population and design a field applicable diagnostic assay for its monitoring.'

They took mosquitoes from Pahou in Benin, which were resistant to DDT and pyrethroids, and mosquitoes from a laboratory fully susceptible strain and did a genome wide comparison study. They identified the GSTe2 gene as being upregulated - producing a lot of protein - in Benin mosquitoes.

They found that a single mutation (L119F) changed a non-resistant version of the GSTe2 gene to a DDT resistant version. They designed a DNA-based diagnostic test for this type of resistance (metabolic resistance) and confirmed that this mutation was found in mosquitoes from other areas of the world with DDT resistance but was completely absent in regions without. X-ray crystallography of the protein coded by the gene illustrated exactly how the mutation conferred resistance, by opening up the 'active site' where DDT molecules bind to the protein, so more can be broken down. This means that the mosquito can survive by breaking down the poison into non-toxic substances.

They also introduced the gene into fruit flies (Drosophila melanogaster) and found they became resistant to DDT and pyrethroids compared to controls, confirming that just this single mutation is enough to make mosquitoes resistant to both DDT and permethrin.

Wondji says: 'For the first time, we have been able to identify a molecular marker for metabolic resistance (the type of resistance most likely to lead to control failure) in a mosquito population and to design a DNA-based diagnostic assay. Such tools will allow control programs to detect and track resistance at an early stage in the field, which is an essential requirement to successfully tackle the growing problem of insecticide resistance in vector control. This significant progress opens the door for us to do this with other forms of resistance as well and in other vector species.'


'/>"/>
Contact: Clare Bebb
c.bebb@liv.ac.uk
44-015-170-53135
Liverpool School of Tropical Medicine
Source:Eurekalert  

Related biology news :

1. Study by UC Santa Barbara researchers suggests that bacteria communicate by touch
2. UC Santa Barbara researchers discover genetic link between visual pathways of hydras and humans
3. Researchers attempt to solve problems of antibiotic resistance and bee deaths in one
4. UNH researchers find African farmers need better climate change data to improve farming practices
5. Ottawa researchers to lead world-first clinical trial of stem cell therapy for septic shock
6. Researchers uncover molecular pathway through which common yeast becomes fungal pathogen
7. Researchers print live cells with a standard inkjet printer
8. Columbia Engineering and Penn researchers increase speed of single-molecule measurements
9. Researchers reveal how a single gene mutation leads to uncontrolled obesity
10. Researchers discover novel therapy for Crohns disease
11. New paper by Notre Dame researchers describes method for cleaning up nuclear waste
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Researchers at LSTM crack the genetic secret of mosquito resistance to DDT and ITNs
(Date:3/20/2017)... , March 20, 2017 At this year,s ... -based biometrics manufacturer DERMALOG. The Chancellor came to the DERMALOG stand ... is this year,s CeBIT partner country. At the largest German biometrics ... in use: fingerprint, face and iris recognition as well as DERMALOGĀ“s multi-biometrics ... ...
(Date:3/9/2017)... FRANCISCO and MOUNTAIN VIEW, Calif. ... , "Eating Well Made Simple," and 23andMe , ... help guide better food choices.  Zipongo can now provide ... their food preferences, health goals and biometrics, but also ... certain food choices. Zipongo,s personalized food decision ...
(Date:3/2/2017)... , March 2, 2017 Summary ... better understand Merck KGaA and its partnering interests and ... https://www.reportbuyer.com/product/3605601/ Description The Partnering Deals and Alliance ... partnering activity of one of the world,s leading life ... prepared upon purchase to ensure inclusion of the most ...
Breaking Biology News(10 mins):
(Date:3/23/2017)... 2017  BioPharmX Corporation (NYSE MKT: BPMX), a ... market, today reported financial results for the quarter ... provide an update on the company,s clinical development ... "We are pleased to report that last year ... President Anja Krammer. "We achieved key clinical milestones ...
(Date:3/23/2017)... 2017 According to a report by Transparency ... fragmented due to the presence of a large pool of participants; ... Fisher , and Sigma-Aldrich, compete with each other in this market. ... more than 76% of this market in 2016.  ... As of now, a large number ...
(Date:3/22/2017)... , March 22, 2017 Regeneron Pharmaceuticals, Inc. ... Regeneron Genetics Center (RGC), U.K. Biobank and GSK to generate ... U.K. Biobank resource. The initiative will enable researchers to gain ... medicines for a wide range of serious and life threatening ... ...
(Date:3/22/2017)... CAMBRIDGE, Mass. , March 22, 2017 ... announced that it has eclipsed the 130 million covered ... Cross Blue Shield of Texas . ... stages, the Company continues to enjoy strong payor acceptance ... of its clinical programs and genetic counseling, its industry-leading ...
Breaking Biology Technology: