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:5/16/2016)... , May 16, 2016   EyeLock LLC , ... announced the opening of an IoT Center of Excellence ... and expand the development of embedded iris biometric applications. ... level of convenience and security with unmatched biometric accuracy, ... identity aside from DNA. EyeLock,s platform uses video technology ...
(Date:5/3/2016)... , May 3, 2016  Neurotechnology, a ... the MegaMatcher Automated Biometric Identification System (ABIS) ... large-scale multi-biometric projects. MegaMatcher ABIS can process multiple ... using any combination of fingerprint, face or iris ... MegaMatcher SDK and MegaMatcher Accelerator , ...
(Date:4/26/2016)... LONDON , April 26, 2016 ... EdgeVerve Systems, a product subsidiary of Infosys (NYSE: ... a partnership to integrate the Onegini mobile security ... (Logo: http://photos.prnewswire.com/prnh/20151104/283829LOGO ) The ... enhanced security to access and transact across channels. ...
Breaking Biology News(10 mins):
(Date:6/27/2016)... 27, 2016  Liquid Biotech USA ... of a Sponsored Research Agreement with The University ... (CTCs) from cancer patients.  The funding will be ... correlate with clinical outcomes in cancer patients undergoing ... then be employed to support the design of ...
(Date:6/24/2016)... , June 24, 2016 Epic ... sensitively detects cancers susceptible to PARP inhibitors by ... tumor cells (CTCs). The new test has already ... therapeutics in multiple cancer types. Over ... DNA damage response pathways, including PARP, ATM, ATR, ...
(Date:6/23/2016)... ... June 23, 2016 , ... Mosio, a leader in ... Trials Patient Recruitment and Retention Tips.” Partnering with experienced clinical research professionals, Mosio ... practical tips, tools, and strategies for clinical researchers. , “The landscape of how ...
(Date:6/23/2016)... 2016 /PRNewswire/ - FACIT has announced the creation ... biotechnology company, Propellon Therapeutics Inc. ("Propellon" or "the ... a portfolio of first-in-class WDR5 inhibitors for the ... WDR5 represent an exciting class of therapies, possessing ... for cancer patients. Substantial advances have been achieved ...
Breaking Biology Technology: