Gos Micklem and colleagues published a paper in Genome Biology in March, 'Expression of multiple horizontally acquired genes is a hallmark of both vertebrate and invertebrate genomes', in which they demonstrate how they were able to take advantage of the recent availability of a number of high-quality genomes to examine horizontal gene transfer in 40 animal species.
DNA passing from parent to offspring - through vertical gene transfer - is well-known. Horizontal gene transfer, which involves the movement of genetic material between different species, is accepted in single-celled organisms such as bacteria, but its existence in higher organisms, including animals, is less well established, and is controversial in humans.
Genome-wide comparative and phylogenetic analyses showed that HGT in animals typically gives rise to tens or hundreds of active ‘foreign’ genes. Fruit flies and nematodes have acquired these 'foreign' genes throughout their evolution, whilst humans and other primates have gained relatively few since their common ancestor. The research has resolved the controversy surrounding previous evidence of HGT in humans, and provides at least 33 new examples of horizontally acquired genes. Humans have at least 145 genes derived from other species, including bacteria, algae and fungi. Many have been integrated into the DNA of our remote ancestors for millions of years, but the function of most of them is not currently known.
>> Read the [free-access] paper here
The article has received worldwide media coverage : for example see this article in the Economist
Image above: Phylogenetic tree for the human gene HAS1. The human gene under analysis is shown in orange, proteins from chordates are in red, other metazoa in black, fungi in pink, plants in green, protists in grey, archaea in light blue and bacteria in dark blue.