evaluation of the mtdna-coii region based species specific assay for identifying members of the anopheles culicifacies species complex.

b a ckground: anoph eles culicifacies, a major malarial vector has been recognized as a complex of five sibling species, a, b, c, d and e. these sibling species exhibit varied vectorial capacity, host specificity and susceptibility to malarial parasites/ insecticides. in this study, a pcr assay developed earlier for distinguishing the five individual species was validated on samples of a n . culicifacies collected from various parts of india. m e t hods: the samples were initially screened using the rdna-its2 region based primers which categorised the samples into either a/d group or b/c/e group. a proportion of samples belonging to each group were subjected to the mtdna-coii pcr assay for identifying individual species. results: among the 615 samples analysed by rdna-its2 pcr assay, 303 were found to belong to a/d group and 299 to b/c/e group while 13 turned negative. among 163 samples belonging to a/d group, only one sample dis- played the profile characteristic of species a and among the 176 samples falling in the b/c/e group, 51 were identi- fied as species b, 14 as species c and 41 as species e respectively by the mtdna-coii pcr assay. samples exhib- iting products diagnostic of b/c/e, when subjected to pcr-rflp assay identified 15 samples as species e. conclusion: validation of the mtdna-coii pcr assay on large number of samples showed that this technique can- not be used universally to distinguish the 5 members of this species complex, as it has been designed based on mi- nor/single base differences observed in the coii region.