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.
Markers previously associated with CAD only in Europe are highlighted in blue, in Caucasians together with African Americans and Chinese in black and in North Africa in red.
