. Author manuscript; available in PMC: 2013 Apr 1.
Published in final edited form as: Genes Immun. 2012 Sep 6;13(7):566–572. doi: 10.1038/gene.2012.40
Users may view, print, copy, download and text and data- mine the content in such documents, for the purposes of academic research, subject always to the full Conditions of use: http://www.nature.com/authors/editorial_policies/license.html#terms