#blood_group__bloodgroup__blood_type__bloodtype  people whose blood (usually just the red blood cells) has the same antigens
  supertype:  people  (plural) any group of human beings (men or women or children) collectively; "old people"; "there were at least 200 people in the audience"
  subtype:  group_A__A__type_A  the blood group whose red cells carry the A antigen
  subtype:  group_B__B__type_B  the blood group whose red cells carry the B antigen
  subtype:  group_AB__AB__type_AB  the blood group whose red cells carry both the A and B antigens
  subtype:  group_O__O__type_O  the blood group whose red cells carry neither the A nor B antigens; "people with type O blood are universal donors"
  subtype:  Rh-positive_blood_type__Rh_positive  the blood group (approximately 85% of people) whose red cells have the Rh factor (Rh antigen)
  subtype:  Rh-negative_blood_type__Rh_negative  the blood group whose red cells lack the Rh factor (Rh antigen)

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