This statement is true. The **I antigen** is formed from the linear **i antigen** by the action of the **I-branching enzyme (β1,6-N-acetylglucosaminyltransferase)**. This enzyme is encoded by the **GCNT2 gene**. Mutations in this gene result in the rare adult **i phenotype**, where individuals retain strong i antigen expression on their red cells into adulthood and have weak or absent I antigen. This phenotype can be associated with congenital cataracts.

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Zambia

• Naomi Miselo – 31 pts

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