In evolutionary biology, an orphan gene is a gene that has limited phylogenetic distribution. This also means that these genes lack detectable homology to organisms outside such phylogenetic distribution. In many cases homology is determined by sequence similarity, shared domains or synteny.
The two possible modes for the generation of orphan genes are duplication followed by quick divergence, and de novo evolution from non-coding DNA.
In bacterial literature, orphan genes are also referred to as ORFans, a play on open reading frame.
Read more about Orphan Gene: Definitions, Properties, Significance in Evolutionary Biology
Famous quotes containing the word orphan:
“A man should not go where he cannot carry his whole sphere or society with him,Mnot bodily, the whole circle of his friends, but atmospherically. He should preserve in a new company the same attitude of mind and reality of relation, which his daily associates draw him to, else he is shorn of his best beams, and will be an orphan in the merriest club.”
—Ralph Waldo Emerson (1803–1882)