Initial Finding of CYP9M10 Gene Haplotype in Culex Quinquefasciatus-Permethrin Resistant Isolate from Natural Population of Central Java Province, Indonesia

Culex is a mosquito genus which widely distributed in the tropical, subtropical and temperate climates, both in urban and rural areas all over the world. Culex mosquitoes, especially Culex quinquefasciatus, are the main vector of filariasis. Thus, public health prevention is mainly directed to control these species and the chemical control is the most widely used approach. However, unfavourable effects of such control to the C. quinquefasciatus population have been known in the form of resistance and emergence of this resistance to various insecticides has been reported in many countries.

The metabolic resistance in mosquitoes occurs through the expression of P450 gene family. One of the P450 families is CYP9M10 gene. Partial analysis of the CYP9M10 gene sequences C. quinquefasciatus mosquito reveals the differences between susceptible and resistant alleles. This study was started from the bioassay test of C. quinquefasciatus mosquitoes from five filariasis-endemic areas in Central Java and was continued on the molecular analysis of CYP9M10 gene.

The results of resistance analysis using bioassay test showed that the C. quinquefasciatus mosquito which has been isolated in Central Java showed high levels of resistance against permethrin 0.75% when mortality rates ranged from 4.8% to 21.6%.

On the other hand, the molecular analysis revealed three types of haplotypes. The third haplotype had the highest frequency and it exhibited sequence pattern change in the CYP9M10 gene altering the susceptible strain into a resistant one.