They proliferate by replicative transposition and can make up a large fraction of the genome. The complex interactions between transposable elements and the host genes and genomes are just being appreciated.
Transposable elements are powerful genetic tools for basic research and practical applications.
One focus of my research is on the basic molecular genetics of transposable elements in mosquitoes. We have so far discovered more than 30 families of transposable elements in the yellow fever mosquito, Aedes aegypti. Many of these novel transposable elements are associated with genes or other repetitive elements. We are now trying to further understand their organization, distribution, and transpositional behavior in relation to host genes and genomes. We are comparing similar families of transposable elements in different mosquitoes and in a broad range of organisms to understand the evolution of these elements as well as their host genomes.