This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pathology
[{'content': 'Hereditary spherocytosis is due to deficiency - \nSelect and explain. \nA. Spectrin, B. Invertin, C. Cytokeratin, D. All of the above', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Hereditary spherocytosis (HS)\n\nHereditary spherocytosis is an inherited disorder, caused by intrinsic defects in the red cell membrane that is characterized by the production of red cell that is sphere-shaped rather than a biconcave doughnut-shaped, and therefore are sequestrated in spleen and destroyed there.\n\nA structural defect in Hereditary spherocytosis\n\nMembrane-cytoskeleton that lies closely opposed to the internal surface of the plasma membrane, is responsible for elasticity and maintenance of RBC shape.\nMembrane skeleton consists :\n\n\n\nSpectrin\xa0→The chief protein component.\n\n\nAnkyrin and band 4.2\xa0→ Binds spectrin to band 3\n\n\nBand 3 → A transmembrane ion transport protein.\n\n\nBand 4.1 → Binds spectrin to glycophorin A, a transmembrane protein.\n\n\n\nHereditary spherocytosis is caused by a variety of molecular defects in genes that code for any of the following:-\nAnkyrin → Most common\nBand 3 → Second most common\nSpectrin CI\nBand 4.2\n\n\n\nHereditary spherocytosis is acquired as autosomal dominant in the majority of the cases. In some cases, the autosomal recessive pattern of inheritance is seen.', 'role': 'assistant'}]