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': 'Chediak Higashi syndrome is characterized by following except - \nSelect and explain. \nA. Is autosomal recessive disorder, B. Mutation in LYST gene, C. Effective phagolysosome formation., D. Oculocutaneous albinism', 'role': 'user'}, {'content': "Answer: C \nExplanation: Chediak Higashi syndrome\n\nIt is an autosomal recessive disorder.\nChediak higashi syndrome is caused due to a mutation\xa0in the LYST gene.\nThis gene provides instructions for making a protein,\xa0known as lysosomal trafficking regulator. This\xa0protein plays a role in transport of materials into lysosomes.\nLysosomes contain several enzymes. They use these enzymes to kill various microorganism, break down\xa0several toxins.\nDuring phagocytosis, lysosomes fuse with phagosome, forming a phagolysosome. Once the phagolysosomes are\xa0formed, lysosomes secrete enzymes to kill the bacterias.\nMutation\xa0in the LSYT protein disrupts the size, structure and function\xa0of lysosomes. Lysosomes cannot\xa0fuse with phagosome to form phagolysosome. Thus this syndrome is a disease with impaired\xa0bacteriolysis due to impaired phagolysosome formation.\nAs a result, most people with the chediak higashi syndrome have repeated and persistent infections, starting\xa0in infancy or early childhood. These infections\xa0are life-threatening,\nBesides, the granules of lysosomes, the secretory / storage granules of various other cells are also\xa0affected.\nThe other cells involved are - Melanosomes of melanocytes, Dense bodies of platelets, Granules of\xa0Schwann cells.\nThere are giant primary granules in neutrophils and other granules bearing cells.\nIn pigment cells called melanocytes, the melanosome becomes abnormally large so there is reduced\xa0production\xa0of melanin. Thus people with Chediak Higashi syndrome have oculocutaneous albinism i.e\xa0the colour of skin, hair and eye is reduced.\xa0\nAbnormality in platelets produces bleeding disorders.\nDefective\xa0in platelets produce bleeding disorders.\nDefective\xa0granules in Schwann cells lead to neurological symptoms e.g. peripheral neuropathy,\nMost children with Chediak\xa0Higashi syndrome ultimately\xa0reach a stage of the disorder known as\xa0accelerated phase, (lymphoma-like a stage).\nThis severe phase of the disease is thought to be triggered by viral infection\xa0(E.B.virus). In the\xa0accelerated phase, defective\xa0white blood cells divide uncontrollably and invade many of the body's\xa0organs.\nThe accelerated phase is associated with fever, episodes of abnormal bleeding, overwhelming infections\xa0and organ failure. They are usually life-threatening and lead to death.", 'role': 'assistant'}]