Overproduced esterases in Culex pipiens quinquefasciatus (Diptera : Culicidae) from Vietnam

The electrophoretic polymorphism of loci encoding for 10 enzymes was studie d in Culex p. quinquefasciatus Say from six localities of Vietnam. The anal ysis of 11 "neutral genes" showed that differentiation among samples was lo w, but significant (Fst = 0.06), and significantly related to geographic di stance between sample sites. These results are similar to those observed in other countries (Europe and west Africa). A single type of overproduced es terases (A2-B2) was observed, and its frequency was high (60-100%) in all s amples. This situation is in sharp contrast with that observed in other cou ntries of South East Asia (China, South Korea and Japan), where two or more types of overproduced esterases have been reported. A map summarizing the geographic distribution of Asian Cx. p. quinquefasciatus with overproduced esterases is provided.