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.
Takahata N, Slatkin M.Takahata N, et al. Among authors: slatkin m.Proc Natl Acad Sci U S A. 1984 Mar;81(6):1764-7. doi: 10.1073/pnas.81.6.1764.Proc Natl Acad Sci U S A. 1984.PMID: 6584909Free PMC article.