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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Down syndrome, All are seen except -
assistant
The correct answer is  Ans. is 'c' i.e., t (11:14) [Ref: Nelson 17th/e Chapter 18o In 95% of cases of Down syndrome-trisomy of 21.o Extra chromosome is of maternal in origin,o 1 % have mosaic with some all have 46 chromosome,o 4% have robertsonian translocation.t(13:21)t(14:21)t(15:21)o Very rarely long arm of chromosome 21 is triplicate (Partial trisomy).