An official website of the United States government
The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before
sharing sensitive information, make sure you’re on a federal
government site.
The site is secure.
The https:// ensures that you are connecting to the
official website and that any information you provide is encrypted
and transmitted securely.
Schmitz RJ, Sung S, Amasino RM.Schmitz RJ, et al.Proc Natl Acad Sci U S A. 2008 Jan 15;105(2):411-6. doi: 10.1073/pnas.0710423104. Epub 2008 Jan 4.Proc Natl Acad Sci U S A. 2008.PMID: 18178621Free PMC article.