FRIDAY, 11 MAY 2007As the first genome sequence of a metatherian mammal, or marsupial, to be published, this provides a unique insight into evolutionary genetics.
Marsupials represent one of the three major groups of modern mammals, along with placental mammals like ourselves, and monotremes, which lay eggs. All previously sequenced mammalian genomes have come from placental species.
Comparative analyses of genomes can now be extended using the opossum, inevitably shedding light on human, and other mammalian genetics.
The opossum genome promises to provide evidence of the genetic changes which have caused the morphological and physiological traits of the marsupial lineage, since their divergence 180 million years ago. Analysis has already offered insights into theories surrounding the evolution of the immune system and X chromosomes.
Of equal importance is the invaluable addition this information will make to the investigations already carried out on M. domestica. Cancer research uses the opossum as a unique model for malignant melanoma, as it seems to be as sensitive to ultraviolet radiation as humans.
Regenerative medicine concerning spinal cord and peripheral nerve injuries could also benefit, as the species has a remarkable ability to regenerate, by which the spinal cord of young opossums can heal after being cut through.
The opossum genome sequence provides support for an emerging general model of chromosomal evolution in mammals. Sequencing of additional metatherian genomes is now necessary to detect metatherian specific protein-coding and non-coding elements.
Paper in Nature
Written by Amy Chesterton