Intestinal alkaline phosphatase is more commonly seen in secretors of which blood groups?

• A. Secretors of blood group A
• B. Secretors of blood groups B and O
• C. Secretors of blood group AB
• D. Non-secretors

Answer: (B)

Intestinal alkaline phosphatase (IAP) activity in secretions is influenced by ABH secretor status—the presence of ABH antigens in mucosal secretions. In secretors who express the H antigen in secretions, particularly those with B and O phenotypes, IAP activity tends to be higher and more detectable. A and AB secretors have different glycosylation patterns that can reduce the amount or detectability of IAP in secretions. So, IAP is more commonly seen in secretors of blood groups B and O.