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| In this lab we conduct molecular evolution research through bioinformatics methods. The current focus of our research is on the origin and evolution of new genes and gene loss. We are examining these phenomena in two widely different groups of organisms: vertebrates and poxviruses. |
| Organisms innovate, differentiate and adapt through the gain, loss and relocation of genes in their genome. Analysis of the recently sequenced chicken genome revealed many differences in the gene content of vertebrate genomes. Gene gain during vertebrate evolution has been associated with the evolution of the ape brain (the GLUD2 gene involved in neurotransmitter flux was acquired about 23 million years ago), the development of adaptive immunity (the RAG1/2 genes that increase the coding capacity of the MHC were acquired by horizontal gene transfer from bacteria), and disease (the apolipoprotein(a) gene was acquired by mammals and is associated with cholesterol build-up on artery walls). Gene loss has been associated with disease (e.g., the absence of the urate oxidase gene in humans and great apes results in a susceptibility to kidney stones), and is also a mode of genomic differentiation. It has also been postulated that in some cases new genes may exist in close physical clusters (in terms of their position on the chromosome) which may have a role in their function, for example by facilitating concerted regulation of expression or grouping genes involved in the same metabolic pathway. We are studying genomic sequence available from many vertebrates in order to examine the phylogenetic distribution of genes present in each vertebrate lineage and to examine the molecular evolution of genes that have been gained recently in the vertebrate lineage. |
| Poxviruses have simple genomes amenable to analysis and are therefore a useful system to study. Many different members of the poxvirus group are important infectious agents in humans and other vertebrates (this group includes smallpox and myxomatosis) and so a greater understanding of their evolution may also be useful for understanding their pathogenicity and host specificity. The properties of the origin and evolution of new genes in poxviruses are expected to be different from the properties in vertebrate genomes both because of the comparative simplicity of poxvirus genomes, and also because of the differences in their life cycle (for example, the fact that the viruses are intracellular parasites is likely to make horizontal gene transfer, or gene capture from the host, a more frequent occurrence that in vertebrates). |