Introduction to the ABO Blood Group


The ABO blood group system is the most important in transfusion medicine. This presentation covers basic ABO inheritance, antigen production and expression, and weak subgroups.

Originally published on September 4, 2018

Lecture Presenter

Justin R. Rhees, MS, MLS(ASCP)CM, SBBCM

Justin R. Rhees, MS, MLS(ASCP)CM, SBBCM

Assistant Professor, Medical Laboratory Sciences
Weber State University

Justin received his M.S. Degree in Laboratory Medicine and Biomedical Science at the University of Utah. He is a Specialist in Blood Bank Technology, board certified by the American Society for Clinical Pathology (ASCP), and is an active member of AABB, the South Central Association of Blood Banks (SCABB), and the American Society for Clinical Laboratory Science (ASCLS).


After this presentation, participants will be able to:

  • Describe the biochemistry and production of the A, B, and H antigens.
  • Compare and contrast the subgroups of the A and B blood types.
  • Describe two lectins that can be used to aid in correct ABO typing.
  • Given the results of forward and reverse ABO typing, correctly interpret the patient’s ABO group and identify patterns of discrepancy.

Sponsored by:

University of Utah School of Medicine, Department of Pathology, and ARUP Laboratories