Evidence that a new function evolved from an old gene

Biologists have long supposed that new abilities of living things have come about when new proteins, produced by new genes, modified from pre-existing genes, make such abilities possible. The new genes are thought to come from accidental duplication of a DNA sequence, done so that it is passed on to the offspring. Such accidental events are known to have occurred, and thought to have occurred many many times. But documented examples of such a process in nature, leading to a new function, have been rare or non-existent.

A press release from the University of Illinois indicates that there is good evidence for a specific example. The example is that a gene which helps a fish to survive Antarctic temperatures appears to have evolved from a duplicated pre-existing gene coding for a protein named sialic acid synthase.

The press release was published because a research article, in the Proceedings of the National Academy of Sciences, details the research findings. Since the PNAS does not allow general access to its on-line publications without a price, I have not seen the original work. The PNAS has long been an important journal, and many significant findings have been first disseminated through it. Most likely, this one will join them. It sounds quite important.

Here and here are more comments on the original article.