Skip to main content
Download PDF

Development and application of a tri-allelic PCR assay for screening Vgsc-L1014F kdr mutations associated with pyrethroid and organochlorine resistance in the mosquito Culex quinquefasciatus

Parasites & Vectors volume 12, Article number: 232 (2019) Cite this article

Abstract

Background

Culex quinquefasciatus has a widespread distribution across tropical and sub-tropical regions, and plays an important role in the transmission of vector-borne diseases of public health importance, including lymphatic filariasis (LF) and multiple arboviruses. Increased resistance to insecticides threatens the efficacy and sustainability of insecticide-based anti-vector interventions which mitigate the burden of mosquito transmitted diseases in endemic regions. In C. quinquefasciatus two non-synonymous voltage gated sodium channel (Vgsc) variants, both resulting in a leucine to phenylalanine change at codon 1014, are associated with resistance to pyrethroids and DDT. This tri-allelic variation has compromised the ability to perform high-throughput single-assay screening. To facilitate the detection and monitoring of the Vgsc-1014 locus in field-caught mosquitoes, an Engineered-Tail Allele-Specific-PCR (ETAS-PCR) diagnostic assay was developed and applied to wild mosquitoes from Brazil, Tanzania and Uganda.

Results

This new cost-effective, single-tube assay was compared to two, well-established, genotyping approaches, pyrosequencing and TaqMan. The ETAS-PCR assay showed high specificity for discriminating the three alleles at Vgsc-L1014F, with genotyping results strongly correlated with pyrosequencing and TaqMan results (98.64% and 100% respectively).

Conclusions

Our results support the utility of the ETAS-PCR/Vgsc-1014 diagnostic assay, which stands as an effective alternative for genotyping tri-allelic variants.

Background

The mosquito Culex pipiens quinquefasciatus (hereafter C. quinquefasciatus) acts as a vector of several pathogens in both tropical and temperate environments [1]. In many tropical/sub-tropical regions C. quinquefasciatus is the primary vector of lymphatic filariasis (LF) [2,3,4] whilst in subtropical locations, it is a vector of potentially fatal arboviruses e.g. West Nile virus (WNV) and St. Louis encephalitis virus (SLEV) [5,6,7].

Vaccination and mass drug administration (MDA) are the primary methods for reducing the burden of diseases transmitted by C. quinquefasciatus, but insecticide-based vector control is advocated as an important adjunct. For example, vector control has assisted in mitigating the burden of transmission of arboviruses where immunization campaigns are challenging, such as in rural settlements [8,9,10].

The effectiveness of insecticide-based vector control is threatened by the increased insecticide resistance detected across the globe [11, 12] with the increased resistance to pyrethroids especially worrying as it is the most common active ingredient used to control adult mosquitoes through indoor sprays, outdoor fogs and treated bednets [13].

In C. quinquefasciatus as well as in other mosquitoes of public health importance pyrethroid and DDT-resistance has been associated with two major mechanisms; overexpression of detoxification genes [14,15,16] and a variety of alleles in the voltage-gated sodium channel (Vgsc) gene, called knockdown resistance (kdr) mutations, such as the Vgsc-1014F [17,18,19]. Consequently, developing molecular tools to detect and monitor resistance-alleles at this locus is imperative for the study of the evolution of resistance, and may also assist programme managers in the rational deployment of insecticides.

Several diagnostic tests for typing kdr mutations have already been developed and applied in Culex, Anopheles and Aedes species [20,21,22]. Whilst many rely on standard PCR methods [23,24,25,26], over the past few years there has been an increase in the use of high-throughput methods such as quantitative PCR (e.g. TaqMan allele-specific and melt curve analysis) and pyrosequencing [18, 21, 27].

Regardless of methodology, most assays are designed to perform bi-allelic discrimination, and there are a limited number of low-cost approaches for typing tri-allelic mutations (e.g. [20, 24, 28]) such as the alternative codons (TTA/TTT/TTC) at locus Vgsc-1014 already reported in C. quinquefasciatus populations from Africa and Asia [18, 21, 29].

To address this limitation, we designed and applied a new diagnostic assay, ETAS-PCR (Engineered-Tail Allele-Specific-PCR), which runs under standard PCR conditions, to type tri-allelic variation at Vgsc-1014. Samples of field-caught mosquitoes from Brazil, Tanzania and Uganda were genotyped using the ETAS-PCR/Vgsc-1014 assay along with pyrosequencing and TaqMan allele-discrimination to assess concordance.

Methods

Sampling

A total of 183 field-caught and pyrethroid- or DDT-selected C. quinquefasciatus individuals from Brazil, Tanzania and Uganda were genotyped. Mosquitoes from Campina Grande (7°13′50″S, 35°52′52″W), Paraíba, Brazil were collected in 2016 using 50 ovitraps, one per dwelling randomly distributed within a single neighbourhood. Blood-fed mosquitoes from Mwanza, Tanzania (02°28′S, 32°55′E) were collected from inside houses using a manual aspirator in 2013. Field-caught mosquitoes from Tororo (0°40′41.62″N, 34°11′11.64″E) and Jinja (0°26′ 52.285″N, 33°12′9.403″E), Uganda, were collected in 2012 while Tororo insecticide exposed mosquitoes were phenotyped using insecticide bioassays as described previously [14, 21]. Additionally, 12 specimens from Uganda, genotyped by Sanger sequencing were used as a control [27].

Genomic DNA of individual mosquitoes was isolated using the DNeasy Kit (Qiagen, United Kingdom) and samples were confirmed as C. quinquefasciatus through a diagnostic PCR assay [30].

ETAS-PCR assay design

Primer design

Genetic variation in primer-binding sites could result in null alleles and thereby erroneous PCR genotyping. Therefore, conserved regions in the vicinity of the Vgsc-1014 locus were selected from an alignment of 10 C. quinquefasciatus sequences from distinct geographic regions (Additional file 1: Figure S1), and 6 sequences from other Culex pipiens subspecies: C. pipiens quinquefasciatus, Saudi Arabia, Thailand, Uganda and USA; and C. pipiens pallens and C. pipiens pipiens from China and USA, respectively (see Additional file 1: Figure S2 for GenBank accession numbers).

Development of the ETAS-PCR/Vgsc1014 assay

The ETAS-PCR/Vgsc-1014 multiplex-assay is a single PCR reaction, followed by an endonuclease digestion. The strategy for amplification and allelic-discrimination of the three alternative alleles is depicted in Fig. 1a.

Fig. 1
figure 1

Allele-specific PCR (AS-PCR) for genotyping tri-allelic Vgsc-L1014F variation in C. quinquefasciatus. a Schematic representation of the ETAS-PCR/Vgsc-1014 assay design with primer locations and predicted size of PCR products. Arrows indicate the location of PCR primers; black arrows indicate the universal reverse primer and red, blue and yellow arrows indicate each allele-specific primer (codons TTT, TTA and TTC, respectively). Bases highlighted in grey at the 3′-ends of each specific primer are deliberate mismatches. Blue-asterisks represent the restriction-site of the Eco32I enzyme. Full-length primer sequences are reported in Table 1. b An example of the ETAS-PCR/Vgsc-1014 gel electrophoresis. Lane 1: 100 bp DNA ladder; Lanes 2–4: homozygote for each codon: TTT, TTA and TTC, respectively; Lanes 5–6: heterozygous individuals TTT/TTA, TTA/TTC and TTT/TTC, respectively

Full size image

To amplify a genomic region of 178 bp encompassing the Vgsc-1014 locus by multiplex-PCR reaction, four primers were designed based on a conserved sequence region (Additional file 1: Figure S1) using Primer 3 software [31]; with a universal reverse primer and three specific forward primers (Fig. 1a). For each allele-specific primer, the 3′-end terminus was designed to match exclusively one of the three SNP alleles (TTA, TTT, TTC) at the last base of the Vgsc-1014 codon. To enhance specificity, a deliberate mismatch was also introduced within the last three bases (see Fig. 1a).

To allow allelic discrimination by agarose gel electrophoresis, three 56 bp engineered-tails were synthesized at the 5′-end of the AS forward primer, differing from each other by the engineered position of an Eco32I restriction site (5′-GATATC-3′), which was introduced at distinct points of each tail (Fig. 1a). Thus, after digestion of the 234 bp ETAS-PCR amplified products, each alternative allele has a distinct fragment length (Fig. 1b): TTT (181 bp), TTA (206 bp) and TTC (231 bp).

ETAS-PCR/Vgsc-1014 amplification, endonuclease digestion and genotyping

The ETAS-PCR/Vgsc-1014 multiplex reaction was performed in a total volume of 25 µl containing 10 ng of gDNA, 200 µM each dNTP, 1× PCR buffer, 0.2 units HotStartTaq DNA polymerase (Qiagen), 0.6 µM universal reverse primer Vgsc-1014/R, 0.35 µM of the specific forward primers (Vgsc-1014/F-T and Vgsc-1014/F-C) and 0.3 µM of the Vgsc-1014/F-A primer (Table 1). After initial denaturation at 95 °C for 15 min, amplification was performed for 40 cycles of 94 °C for 30 s, 59 °C for 30 s, and 72 °C for 30 s, followed by a final extension step of 72 °C for 10 min.

Table 1 Primers used in the ETAS-PCR/Vgsc-1014, pyrosequencing and TaqMan assays for genotyping the Vgsc-L1014F in C. quinquefasciatus mosquitoes. The Eco32I site is underlined
Full size table

After amplification, the ETAS-PCR/Vgsc-1014 multiplex products were digested with FastDigest Eco32I restriction enzyme (Thermo Scientific, United Kingdom) in a final reaction volume of 30 µl including 10 µl of the PCR product, 2 µl of 10× FastDigest Green buffer, 1.5 µl of FastDigest enzyme and 17 µl distilled water. The reaction was incubated at 37 °C for 10 min. Finally, 10 µl of digestion reaction was loaded on a 3% agarose gel.

Vgsc-1014 Screening by pyrosequencing assay

For pyrosequencing genotyping, PCR reactions were performed in a total of 25 µl containing 10 ng of gDNA, 200 µM of each dNTP, 1× PCR buffer, 2.0 mM MgCl2, 0.6 units of HotStartTaq DNA polymerase (Qiagen) and 0.4 µM of primers pyr-Vgsc-F and pyr-Vgsc-R (Table 1) [21]. After initial denaturation at 95 °C for 15 min, PCR amplification was performed for 40 cycles of 94 °C for 30 s, 58 °C for 30 s, and 72 °C for 30 s, followed by a final extension step at 72 °C for 10 min.

The pyrosequencing genotyping was performed using single-stranded PCR products obtained using the PyroMark Q24 Vacuum Prep Workstation then used in pyrosequencing reactions performed using the PyroMark Gold Q96 reagent kit (Qiagen). The sequencing primer and dispensation order are described in Table 1.

Vgsc-1014 genotyping by TaqMan allelic discrimation

Due to the tri-allelic variation in the locus Vgsc-1014, two distinct TaqMan assays are applied in parallel for each sample; one to genotype TTA/TTC alleles and the other to detect TTA/TTT variants [27]. Primers and TaqMan probes are shown in Table 1.

Association between target-site alleles and resistant phenotypes

To verify the presence of Vgsc-1014 alleles in insecticide exposed mosquitoes, 3–5 day-old adult F1 female mosquitoes from Tororo, Uganda, were exposed to three insecticides using WHO papers impregnated with a diagnostic concentration: DDT (4%), lambda-cyhalothrin (0.05%) or deltamethrin (0.05%). Mosquitoes were exposed to DDT and lambda-cyhalothrin for 1 h and to deltamethrin for 4 h, in 4 replicates of 25 non-blood fed mosquitoes at an average temperature of 26 °C and relative humidity of 63%. Control bioassays were performed with 25 mosquitoes exposed to non-insecticide treated papers. Insecticide exposed mosquitoes were then transferred to clean holding tubes and provided with 10% glucose for a 24-h period after which mortality was recorded and alive and dead mosquitoes were collected and individually stored on silica gel.

Results and discussion

To determine if the newly-designed ETAS-PCR/Vgsc-1014 performed consistently across C. quinquefasciatus wild populations, genotyping was conducted on mosquitoes from different continents (Africa and South America). Samples from multiple locations in Africa (n = 75); Uganda (Tororo and Jinja) and Tanzania (Mwanza) were genotyped by pyrosequencing and 74 (98.6%) agreed with the ETAS-PCR/Vgsc-1014 scores, with the single ETAS-PCR discordant result resulting from low PCR efficiency for that sample, which does not allow detection of PCR fragments after digestion. For the TaqMan assay, mosquitoes from Campina Grande, Brazil (n = 24) and pyrethroid-exposed individuals from Tororo, Uganda (n = 84) were genotyped, with 100% agreement to ETAS-PCR/Vgsc-1014.

The ETAS-PCR/Vgsc-1014 genotyping compares extremely well to the standard assays and represents a more convenient alternative for low technology laboratories because it uses relatively inexpensive laboratory methods (standard PCR and agarose-gel electrophoresis) yet allows genotyping of variation at this tri-allelic SNP in a single reaction. For instance, the genotyping cost for ETAS-PCR is around 4.6 and 3.12 times lower compared to TaqMan and pyrosequencing, respectively, based on the minimum chemistry required (e.g. DNA polymerase or master mix, either standard or biotinylated primers or fluorescence probes).

The ETAS-PCR/Vgsc-1014 also addresses limitations reported in other Allelic-Specific PCR (AS-PCR) assays designed for typing triple variants within a codon. For instance, the AS-PCR applied for genotyping Vgsc-L1014F and Vgsc-L1014S in Culex pipiens pallens, can differentiate wild-type from resistance-alleles but lacks the resolution to discriminate between the two resistance alleles [25]. Additionally, the AS-PCR of Chamnanya [32] designed to type Vgsc-1014 in C. quinquefasciatus differentiates only two (TTA and TTT) of the three alleles but can not detect the TTC resistant allele, which we found to be common in Tanzania and Uganda (Table 2) and has been reported elsewhere [29]. Indeed, in mosquitoes from Tororo, Uganda we did detect a high frequency of heterozygous wild-type/resistance-alleles among the phenotypically resistant mosquitoes exposed to either deltamethrin, lambda-cyhalothrin or DDT, for which was recorded a frequency of genotypes harboring at least one resistance-allele ranging from 70.37% to 85.78% (Additional file 2: Table S1).

Table 2 Specificity of ETAS-PCR Vgsc-1014 in comparison to pyrosquencing and TaqMan genotyping
Full size table

Conclusions

Developing tools which are easy to apply, such as the ETAS-PCR/Vgsc-1014, is imperative to detect and monitor resistance-alleles while may also assist decision-making for resistance management.

Availability of data and materials

All data generated or analysed during this study are included in this published article and its additional files.

Abbreviations

LF:

lymphatic filariasis

Vgsc :

voltage gated sodium channel

ETAS-PCR:

engineered-tail allele-specific-PCR

WNV:

West Nile virus

SLEV:

St. Louis encephalitis virus

MDA:

mass drug administration

AS-PCR:

allelic-specific PCR

References

  1. Farajollahi A, Fonseca DM, Kramer LD, Kilpatrick AM. “Bird biting” mosquitoes and human disease: a review of the role of Culex pipiens complex mosquitoes in epidemiology. Infect Genet Evol. 2011;11:1577.

    Article  Google Scholar 

  2. Simonsen PE, Mwakitalu ME. Urban lymphatic filariasis. Parasitol Res. 2013;112:35–44.

    Article  Google Scholar 

  3. Bockarie MJ, Pedersen EM, White GB, Michael E. Role of vector control in the global program to eliminate lymphatic filariasis. Annu Rev Entomol. 2009;54:469–87.

    Article  CAS  Google Scholar 

  4. Behura SK, Lobo NF, Haas B, deBruyn B, Lovin DD, Shumway MF, et al. Complete sequences of mitochondria genomes of Aedes aegypti and Culex quinquefasciatus and comparative analysis of mitochondrial DNA fragments inserted in the nuclear genomes. Insect Biochem Molec. 2011;41:770–7.

    Article  CAS  Google Scholar 

  5. Cornel A, Lee Y, Fryxell RT, Siefert S, Nieman C, Lanzaro G. Culex pipiens sensu lato in California: a complex within a complex? J Am Mosq Control Assoc. 2012;28:113–21.

    Article  Google Scholar 

  6. Molaei G, Huang S, Andreadis TG. Vector–host interactions of Culex pipiens complex in northeastern and southwestern USA. J Am Mosq Control Assoc. 2012;28:127–36.

    Article  Google Scholar 

  7. Hamer GL, Kitron UD, Brawn JD, Loss SR, Ruiz MO, Goldberg TL, et al. Culex pipiens (Diptera: Culicidae): a bridge vector of West Nile virus to humans. J Med Entomol. 2008;45:125–8.

    Article  Google Scholar 

  8. Hills SL, Phillips DC. Past, present, and future of Japanese encephalitis. Emerg Infect Dis. 2009;15:1333.

    Article  Google Scholar 

  9. Addiss D. The 6th Meeting of the global alliance to eliminate lymphatic filariasis: a half-time review of lymphatic filariasis elimination and its integration with the control of other neglected tropical diseases. Parasit Vectors. 2010;3:100.

    Article  Google Scholar 

  10. Rivero A, Vezilier J, Weill M, Read AF, Gandon S. Insecticide control of vector-borne diseases: when is insecticide resistance a problem? PLoS Pathog. 2010;6:e1001000.

    Article  Google Scholar 

  11. Coleman M, Hemingway J, Gleave KA, Wiebe A, Gething PW, Moyes CL. Developing global maps of insecticide resistance risk to improve vector control. Malar J. 2017;16:86.

    Article  Google Scholar 

  12. Moyes CL, Vontas J, Martins AJ, Ng LC, Koou SY, Dusfour I, et al. Contemporary status of insecticide resistance in the major Aedes vectors of arboviruses infecting humans. PLoS Negl Trop Dis. 2017;11:e0005625.

    Article  Google Scholar 

  13. Kleinschmidt I, Bradley J, Knox TB, Mnzava AP, Kafy HT, Mbogo C, et al. Implications of insecticide resistance for malaria vector control with long-lasting insecticidal nets: a WHO-coordinated, prospective, international, observational cohort study. Lancet Infect Dis. 2018;18:640–9.

    Article  Google Scholar 

  14. Martins WFS. Evolutionary genetics of insecticide resistance in Culex quinquefasciatus. PhD Thesis, University of Liverpool. 2015. https://livrepository.liverpool.ac.uk/2047820/. Accessed 5 Jan 2019.

  15. Mitchell SN, Stevenson BJ, Müller P, Wilding CS, Egyir-Yawson A, Field SG, et al. Identification and validation of a gene causing cross-resistance between insecticide classes in Anopheles gambiae from Ghana. Proc Natl Acad Sci USA. 2012;109:6147–52.

    Article  CAS  Google Scholar 

  16. David J-P, Ismail HM, Chandor-Proust A, Paine MJI. Role of cytochrome P450s in insecticide resistance: impact on the control of mosquito-borne diseases and use of insecticides on Earth. Philos Trans R Soc Lond B Biol Sci. 2013;368:20120429.

    Article  Google Scholar 

  17. Scott JG, Yoshimizu MH, Kasai S. Pyrethroid resistance in Culex pipiens mosquitoes. Pestic Biochem Physiol. 2015;120:68–76.

    Article  CAS  Google Scholar 

  18. Jones CM, Machin C, Mohammed K, Majambere S, Ali AS, Khatib BO, et al. Insecticide resistance in Culex quinquefasciatus from Zanzibar: implications for vector control programmes. Parasit Vectors. 2012;5:78.

    Article  CAS  Google Scholar 

  19. Li T, Zhang L, Reid WR, Xu Q, Dong K, Liu N. Multiple mutations and mutation combinations in the sodium channel of permethrin resistant mosquitoes, Culex quinquefasciatus. Sci Rep. 2012;2:781.

    Article  Google Scholar 

  20. Unwin VT, Ainsworth S, Rippon EJ, Paine MJ, Weetman D, Adams ER. Development of a rapid field-applicable molecular diagnostic for knockdown resistance (kdr) markers in An. gambiae. Parasit Vectors. 2018;11:307.

    Article  Google Scholar 

  21. Martins WFS, Wilding CS, Steen K, Mawejje H, Antão TR, Donnelly MJ. Local selection in the presence of high levels of gene flow: evidence of heterogeneous insecticide selection pressure across Ugandan Culex quinquefasciatus populations. PLoS Negl Trop Dis. 2017;11:e0005917.

    Article  Google Scholar 

  22. De LMM, Martins AJ, Andrighetti MTM, Lima JBP, Valle D. Pyrethroid resistance persists after ten years without usage against Aedes aegypti in governmental campaigns: lessons from São Paulo State, Brazil. PLoS Negl Trop Dis. 2018;12:e0006390.

    Article  Google Scholar 

  23. Singh OP, Bali P, Hemingway J, Subbarao SK, Dash AP, Adak T. PCR-based methods for the detection of L1014 kdr mutation in Anopheles culicifacies sensu lato. Malar J. 2009;8:154.

    Article  Google Scholar 

  24. Zhong D, Chang X, Zhou G, He Z, Fu F, Yan Z, et al. Relationship between knockdown resistance, metabolic detoxification and organismal resistance to pyrethroids in Anopheles sinensis. PloS One. 2013;8:e55475.

    Article  CAS  Google Scholar 

  25. Chen L, Zhong D, Zhang D, Shi L, Zhou G, Gong M, et al. Molecular ecology of pyrethroid knockdown resistance in Culex pipiens pallens mosquitoes. PloS One. 2010;5:e11681.

    Article  Google Scholar 

  26. Linss JGB, Brito LP, Garcia GA, Araki AS, Bruno RV, Lima JBP, et al. Distribution and dissemination of the Val1016Ile and Phe1534Cys Kdr mutations in Aedes aegypti Brazilian natural populations. Parasit Vectors. 2014;7:25.

    Article  Google Scholar 

  27. Martins WFS, Subramaniam K, Steen K, Mawejje H, Liloglou T, Donnelly MJ, et al. Detection and quantitation of copy number variation in the voltage-gated sodium channel gene of the mosquito Culex quinquefasciatus. Sci Rep. 2017;7:5821.

    Article  Google Scholar 

  28. Tan WL, Li CX, Wang ZM, Liu MD, Dong YD, Feng XY, et al. First detection of multiple knockdown resistance (kdr)-like mutations in voltage-gated sodium channel using three new genotyping methods in Anopheles sinensis from Guangxi Province, China. J Med Entomol. 2014;49:1012–20.

    Article  Google Scholar 

  29. Wondji CS, De Silva WAPP, Hemingway J, Ranson H, Karunaratne SHPP. Characterization of knockdown resistance in DDT- and pyrethroid-resistant Culex quinquefasciatus populations from Sri Lanka. Trop Med Int Health. 2008;13:548–55.

    Article  CAS  Google Scholar 

  30. Smith JL, Fonseca DM. Rapid assays for identification of members of the Culex (Culex) pipiens complex, their hybrids, and other sibling species (Diptera: Culicidae). Am J Trop Med Hyg. 2004;70:339–45.

    Article  CAS  Google Scholar 

  31. Rozen S, Skaletsky H. Primer3 on the www for general users and for biologist programmers. Methods Mol Biol. 2000;132:365–86.

    CAS  Google Scholar 

  32. Chamnanya S, Somboon P, Lumjuan N, Yanola J. Development of tetra-primer allele specific PCR (tetra-primer AS-PCR) for the detection of L1014F mutation in sodium channel gene associated with pyrethroid resistance in mosquito Culex quinquefasciatus. Am J Med Sci. 2016;49:389.

    Google Scholar 

Download references

Acknowledgments

We would like to thank Henry Mawejje for supporting the field-collections in Uganda. The authors also thank Dr Triantafillos Liloglou and Keith Steen for supporting the pyrosequencing genotyping.

Funding

This study was supported by The Coordination for the Improvement of Higher Education Personnel, CAPES (Grant: BEX-6193). Partial funding for this work came from UEPB/PROPESQ (Grant: 2.08.04.00-8-389/2017-1) and Wellcome Trust Training fellowship in Public Health and Tropical Medicine (Grant: 209305/Z/17/Z) to WFSM.

Author information

Authors and Affiliations

  1. Laboratório de Entomologia Médica e Molecular, Departamento de Biologia, CCBS, Universidade Estadual da Paraíba, Campina Grande, Paraíba, Brasil

    Walter Fabricio Silva Martins & Ana Thayse Vieira Alves

  2. Department of Vector Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, UK

    Walter Fabricio Silva Martins, Annabel Murphy, David Weetman & Martin James Donnelly

  3. Departamento de Genética, CB, Universidade Federal de Pernambuco, Recife, Brasil

    Bárbara Natieli Silva Pereira

  4. Departamento de Farmácia, CCBS, Universidade Estadual da Paraíba, Campina Grande, Paraíba, Brasil

    Ana Thayse Vieira Alves

  5. Laboratório de Interações Insetos-Tóxicos, Departamento de Agronomia e Fitossanidade, Universidade Federal Rural de Pernambuco, Recife, Brasil

    Paulo Geovani Silva Martins

  6. School of Natural Sciences and Psychology, Liverpool John Moores University, Liverpool, UK

    Craig Stephen Wilding

Authors
  1. Walter Fabricio Silva Martins
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Bárbara Natieli Silva Pereira
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Ana Thayse Vieira Alves
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Annabel Murphy
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Paulo Geovani Silva Martins
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. David Weetman
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. Craig Stephen Wilding
    View author publications

    You can also search for this author in PubMed Google Scholar

  8. Martin James Donnelly
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

WFSM conceived, designed the experiments and wrote the paper. WFSM, BNSP, ATVA, AM and PGSM performed the experiments. WFSM and BNSP analysed the data. BNSP, ATVA, AM, PSM, DW and MJD contributed reagents/materials/sample collections. DW, CSW and MJD reviewed the final manuscript. All authors read and approved the final manuscript.

Corresponding author

Correspondence to Walter Fabricio Silva Martins.

Ethics declarations

Ethics approval and consent to participate

No specific permits were required for the described field work as no human participants were involved. Oral consent was obtained from householders prior to collections and no personal details were recorded.

Consent for publication

Not applicable.

Competing interests

The authors declare that they have no competing interests.

Additional information

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Additional files

Additional file 1: Figure S1.

Multiple sequence alignment of the partial fragment of the Vgsc gene across Culex pipiens pipiens, Culex p. quinquefasciatus and Culex p. pallens. Figure S2. Neighbor-joining tree of the partial fragment of the Vgsc gene.

Additional file 2: Table S1.

Allelic and genotypic frequency of Vgsc-1014F in relation to mosquito survival phenotype by deltamethrin, lambda-cyhalothrin or DDT in C. quinquefasciatus from Tororo, Uganda.

Rights and permissions

Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Silva Martins, W.F., Silva Pereira, B.N., Vieira Alves, A.T. et al. Development and application of a tri-allelic PCR assay for screening Vgsc-L1014F kdr mutations associated with pyrethroid and organochlorine resistance in the mosquito Culex quinquefasciatus. Parasites Vectors 12, 232 (2019). https://doi.org/10.1186/s13071-019-3490-z

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1186/s13071-019-3490-z

Keywords

Parasites & Vectors

ISSN: 1756-3305

Contact us