Aptamers are  structured nucleic acids that bind various target molecules. In a recent issue of Chemistry & Biology the Luptak group present the discovery of the first aptamers found in vertebrates, including humans.

 These aptamers bind adenosine using the same fold as was discovered using in vitro selection from random, synthetic libraries twenty years ago, thus representing an unusual case of convergent molecular evolution of a functional RNA.
Former chemistry undergraduates Michael Vu and Stuart Masuda, together with grad student Nora Jameson, biology undergraduate Dana Lin, and research associate Rosa Larralde made the discovery. See also a Preview by Bevilacqua and co-workers (http://www.sciencedirect.com/science/article/pii/S1074552112003766).