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.