This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cytogenetic Disorders, Subject name: Pathology
[{'content': 'Xeroderma pigmentosum is caused due to defect in: (Repeat) \nSelect and explain. \nA. Base pair, B. Nucleotide excision repair, C. Mismatch repair, D. Translocation', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ref: Chapter 7. Neoplasia; page: 275; Robbins and Cot ran Pathologic Basis of Disease: 8t>? editionExplanation:* Defective DNA - repair syndromes are set of syndrome due to defect in DNA repair genes and resultant DNA instability.* These are autosomal recessive in inheritance and include:Xeroderma pigmentosumBloom syndromeAtaxia telangiectasia.* Whereas, HNPCC is associated with inactivation of DNA mismatch repair gene, resulting in increased susceptibility to colon cancer, and cancers of Endometrium, ovary etc.,* Example for Base pair defect is Sickle cell anemia; example for Translocation defect is Philadelphia chromosome in CML - t (9:22).', 'role': 'assistant'}]