Partner study description
Specimens were collected along the Gambia River from the western coastal region of The Gambia (1), in August 2006. An. gambiae and An. coluzzii specimens were identified to species following the PCR-RFLP protocol (2) using DNA extracted from the mosquito leg. Only An. coluzzii specimens were collected from villages of Tankular (13.417, -16.033) and Kalataba (13.550, -15.617). An. gambiae and An. coluzzii specimens were found in sympatry and collected from villages of Yallal Tankonjala (13.550, -15.700), Sare Samba Sowe (13.583, -15.900) and Hamdalai (13.567, -16.0167). PCR-RFLP protocol also revealed the presence of mosquitoes with hybrid An. gambiae/An. coluzzii genotype in Yallal Tankonjala and Sare Samba Sowe. Collections of indoor daytime-resting half gravid mosquitoes were carried out mainly in human dwellings and, in few cases, in animal shelters. Collections were carried out by pyrethroid and/or paper-cup mouth aspirators from 12 AM to sunset, and kept in vials with desiccant. Ovaries were dissected, maintained into Carnoy fixative (three parts pure ethanol:one part glacial acetic acid) and stored at -20C before polytene chromosome preparations (1) Chromosome scoring was carried out under a phase‐contrast optical microscope. Paracentric inversion karyotypes were scored according to the nomenclature and conventions of (3) and (4).
See Caputo et al. (1) for further details of this study.
1. Beniamino Caputo, Davis Nwakanma, Musa Jawara, Majidah Adiamoh, Ibrahima Dia, Lassana Konate, Vincenzo Petrarca, David J Conway, and Alessandra della Torre. Anopheles gambiae complex along the gambia river, with particular reference to the molecular forms of an. gambiae s.s. Malaria J, 7:182, 2008. https://doi.org/10.1186/1475-2875-7-182
2. C. Fanello, F. Santolamazza, and A. della Torre. Simultaneous identification of species and molecular forms of the anopheles gambiae complex by pcr-rflp. Med Vet Entomol, 16:461–464, December 2002. https://doi.org/10.1046/j.1365-2915.2002.00393.x
3. M. Coluzzi, A. Sabatini, V. Petrarca, and M. A. Di Deco. Chromosomal differentiation and adaptation to human environments in the anopheles gambiae complex. Trans. R. Soc. Trop. Med. Hyg., 73(5):483–497, January 1979. https://doi.org/10.1016/0035-9203(79)90036-1
4. Y. T. Toure, V. Petrarca, S. F. Traore, A. Coulibaly, Maiga H. M., O. Sankare, M. Sow, M. A. Di Deco, and M. Coluzzi. The distribution and inversion polymorphism of chromosomally recognized taxa of the Anopheles gambiae complex in Mali, West Africa. Parassitologia, 40:477–511, 1998. https://pubmed.ncbi.nlm.nih.gov/10645562/
Contributors
Beniamino Caputo (beniamino.caputo@uniroma1.it) Istituto Pasteur Italia–Fondazione Cenci Bolognetti, Dipartimento di Sanita Pubblica e Malattie Infettive, Università di Roma SAPIENZA, Rome, Italy.
Musa Jawara Medical Research Council Unit, The Gambia at the London School of Hygiene & Tropical Medicine (MRCG at LSHTM), Banjul, The Gambia.
Davis C. Nwakanma Medical Research Council Unit, The Gambia at the London School of Hygiene & Tropical Medicine (MRCG at LSHTM), Banjul, The Gambia.
David Conway London School of Hygiene and Tropical Medicine, Keppel Street, Bloomsbury, London WC1E 7HT, UK.
Alessandra della Torre (alessandra.dellatorre@uniroma1.it) Istituto Pasteur Italia–Fondazione Cenci Bolognetti, Dipartimento di Sanita Pubblica e Malattie Infettive, Università di Roma SAPIENZA, Rome, Italy.