The role of DNA insertions in phenotypic differentiation between humans and other primates.

What makes us human is one of the most interesting and enduring questions in evolutionary biology. To assist in answering this question, we have identified insertions in the human genome which cannot be found in five comparison primate species: Chimpanzee, gorilla, orangutan, gibbon, and macaque. A total of 21,269 nonpolymorphic human-specific insertions were identified, of which only 372 were found in exons.

Transposable element invasions.

Transposable elements have an ongoing, largely parasitic interaction with their hosts. We are interested in the timescale of this interaction. In a recent publication, we have examined the sequence divergence between class II DNA transposons from mammalian genomes.

The diversity of class II transposable elements in mammalian genomes has arisen from ancestral phylogenetic splits during ancient waves of proliferation through the genome.

DNA transposons make up 3% of the human genome, approximately the same percentage as genes. However, because of their inactivity, they are often ignored in favor of the more abundant, active, retroelements. Despite this relative ignominy, there are a number of interesting questions to be asked of these transposon families.

Investigation of the origin and spread of a Mammalian transposable element based on current sequence diversity.

Almost half the human genome consists of mobile DNA elements, and their analysis is a vital part of understanding the human genome as a whole. Many of these elements are ancient and have persisted in the genome for tens or hundreds of millions of years, providing a window into the evolution of modern mammals. The Golem family have been used as model transposons to highlight computational analyses which can be used to investigate these elements, particularly the use of molecular dating with large transposon families.