Relationships Among Three House Dust Mites Based on Molecular Data

House dust mites not only live in house dusts but also affect human bodies. Among the many species, D. farinae, D. pteronyssinus, Euroglyphus maynei have been found commonly associated with Ig-E mediated allergic diseases. As a result, there is increasing effort to develop methods for diagnosis and treatment for diseases caused by these species. The present study was to explore the evolutionary relationships among house dust mites. After adult D. farinae were separated and isolated for total RNA extract, the cDNA coding for Der f 1 and Der f 2 were cloned and sequenced. Then amino acid sequences for groups 1 and 2 allergens of two of the most common house dust mites D. pteronyssinus, E. maynei were obtained from databases. Interestingly, homological analysis of amino acid sequences showed that both Der p 1 and Der p 2 from D. pteronyssinus had higher similarities to Eur m 1 and Eur m 2, respectively, than to Der f 1 and Der f 2 from D. farinae. In the phylogenetic trees, D. pteronyssinus clustered with E. maynei but not with D. farinae, although the D. pteronyssinus and D. farinae belonged to the same genus based on morphological taxonomy. It was supposed that D. pteronyssinus be more similar to E. maynei than to D. farinae at evolutional levels.