Population demography of malaria vector Anopheles (Anopheles) pseudopunctipennis from Argentina

DANTUR JURI, M.J.; PRADO IZAGUIRRE, M.J.; NAVARRO, J.C.; CLAPS, G.L.; CONN, J.E.

Washington, USA

Congreso; 58th Annual Meeting of the American Society for Tropical Medicine and Hygiene.; 2009

American Society of Tropical Medicine and Hygiene

Anopheles pseudopunctipennis is an important malaria vector in some areas of America, where this disease is still a problem in public health. Its wide geographical distribution includes several ecologically distinctive areas, only some of which are endemic for malaria transmission. Some markers provide evidence for An. pseudopunctipennis as a complex. In the present study, we analyzed the population structure and demography of An. pseudopunctipennis in two regions of NW Argentina, northern and southern, using cytochrome oxidase subunit I (COI). We identified 41 haplotypes, of which seven were shared among all samples localities, comprising 77% of all individuals examined. A statistical parsimony network showed that haplotype A was the most common and widespread and considered ancestral. The FST values were the highest between two southern localities. The Neighbor Joining tree based on the FST distances was poorly resolved, and did not detect any structure among the NW Argentinian populations. San Roquito (Tartagal) and Potrero Las Tablas were the populations with the highest haplotype diversities in both areas (0.805 and 1.000, respectively). Nucleotide diversity was similar in all populations. The highest average number of nucleotide differences (K) was observed for San Roquito Tartagal (0.00179) and Tucumán Sur (0.00262). GST and NM values showed the pairwise genetic differentiation and the gene flow between different populations. Similar to the FST results, GST detected the highest values between two southern localities. The mismatch distribution in Aguas Blancas and Yuto (northern) and Rosario la Frontera and Tucumán Sur (southern) a smooth unimodal distribution characteristic of a population expansion. The time of the expansion of An. pseudopunctipennis varies among localities but all are during the Pleistocene. In the future we hope to carry on an extensive study including samples of An. pseudopunctipennis from different countries of America to evaluate the possible presence of lineages influenced geographic barriers.