In hereditary spherocytosis, the MOST common protein defect causing the disease in Northern European populations is:

• A Band 3 protein deficiency
• B Ankyrin deficiency ✓
• C Spectrin deficiency (alpha or beta)
• D Protein 4.2 deficiency

Explanation

Ankyrin deficiency (encoded by ANK1 on chromosome 8p) is the most common defect in hereditary spherocytosis in Northern European populations, accounting for approximately 40–65% of cases. Ankyrin links spectrin to band 3, and its loss destabilizes the lipid bilayer causing membrane vesiculation and spherocyte formation. Band 3 mutations are common in Japanese HS patients.

Reference: Robbins & Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.