He reports that Iceland's preliminary round match against Denmark attracted nearly 60 percent of the country's 100, 000 televisions and a share of about 100.

NPR: Sports Beyond The Olympics

When someone joins the register, the charity does a preliminary analysis of their DNA. If they come up as a possible match, they are contacted for a more detailed tissue type analysis that confirms if they are suitable.

BBC: New stem cell matching program for British Asians