You may tag a profile by using the @ symbol and start typing the name of a profile on Geni to tag it to your post. A list of auto-suggested names will appear enabling you to select them. This will insert their profile ID within double square brackets into the text.
If you do not see the person you are trying to tag in the list, you can manually insert their profile ID within those brackets.
Example: To tag George Washington to a discussion, insert his profile ID into double brackets []
Additionally you can tag a person by starting the discussion from that person's profile, under the Discussions tab.