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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Isoantigens are -
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The correct answer is  Isoantigens are antigens found in some but not all members of a species. A species may be grouped depending on the presence of different isoantigens in its members. The best example is human erythrocyte antigens, based on which individuals can be classified into different blood groups. Reference:athanarayan & paniker's 9th edition, pg no: 89 <\p>