Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Possible elements or pathways involved in the OM development are illustrated. Solid lines show pathways for which there is direct evidence. Dashed lines are proposed links.
