This statement is true. The John Milton Hagen (JMH) blood group system antigens (JMH being the primary high-frequency antigen) are carried on the semaphorin 7A (CD108) protein. A unique characteristic of the JMH antigen is that its expression on red blood cells gradually weakens with age, particularly in elderly individuals. The JMH-negative phenotype is extremely rare and can be inherited or acquired (transient loss). Antibodies to JMH are usually IgG and are often found in elderly patients. These antibodies are generally not considered clinically significant; they rarely cause hemolytic transfusion reactions or Hemolytic Disease of the Fetus and Newborn (HDFN). However, they can be a nuisance in the laboratory, causing positive antibody screens that require identification. Understanding this age-related weakening helps in interpreting serological results in older patients.

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Zambia

• Naomi Miselo – 31 pts

• Visual Pathway Lesions
• Positive and Negative Symptoms
• Hallucinations and Delusions
• Antipsychotic Medications
• Emergency: Environmental Emergencies