Rick Hendrick, the NASCAR racing teams owner got involved in helping the National Marrow Program when he developed Leukemia in the '90's. This is the same site linked above but is worth going back to if you haven't read it. There are menus to follow with hot links that explain all the rules, the myths, the procedures.....ie, you can be 60 and donate if you're in good health. And they take money too. Good out fit that has saved many, many, lives.

Hendrick Page but follow the menu stuff to answer all your questions

Spaw