Are you an A, B or O - or even a Duffy? Why you should know your blood type - Daily Mail 21st June 2008

Do you know what blood type you are? If you don't, you're not alone. Although blood type is a fundamental part of our biological make-up, determined by our genes - like having blue eyes or being left-handed - unless you pay for a private test, there are only three ways to find out which you are.

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