රුධිර ගණ පද්ධතිය මත රදාපවතිමින්, මේ ප් රතිදේහජනකයන් ප් රෝටීන, කාබෝහයිඩ්රේට, ග්ල්ය්කෝප් රෝටීන, හෝ ග්ල්ය්කෝලිපිඩ, විය හැකිය. some of these antigens are also present on the surface of other types of cells of various tissues. several of these red blood cell surface antigens can stem from one allele and collectively form a blood group system. blood types are inherited and represent contributions from both parents. a total of 32 human blood group systems are now recognized by the international society of blood transfusion. the two most important ones are abo and the rhd antigen; they determine someone ' s blood type.