DNA for the Taking
Most organisms have a set of genes from birth to death, and that set is the one their sexual parents or asexual parent provided. This is vertical gene transfer. Other organisms collect fragments of DNA from the environment. The collecting organism cell briefly links to the host cell of the fragment DNA and incorporates that DNA. This is horizontal gene transfer.
That may be a gross over-generalization of the process, but it builds a picture.
A South Pacific shrub known as Amborella trichopoda takes horizontal gene transfer to another level. A study by Andrew Alverson, assistant professor of biological sciences, revealed that instead of borrowing chunks of DNA from other plants, Amborella mitochondria acquire whole genomes from green algae. You may think there is some evolutionary advantage to accumulating more and more genes, but it appears these genes do not give Amborella any additional function.
The full story of the research that discovered Amborella’s use of horizontal gene transfer was published in the December issue of the journal Science, but we also have a news release and a research brief in the most recent issue of Research Frontiers.