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Question: Answered & Verified by Expert
A disease caused by an autosomal primary non-disjunction is
BiologyPrinciples of Inheritance and VariationNEETNEET 2017
Options:
  • A Down's syndrome
  • B Klinefelter's syndrome
  • C Turner's syndrome
  • D Sickle cell anemia
Solution:
2068 Upvotes Verified Answer
The correct answer is: Down's syndrome
Non-disjunction is the failure of homologous chromosomes to disjoin or separate and move away to opposite poles. Non-disjunction of the 21st chromosome during oogenesis is the cause of Down's syndrome. It occurs due to the presence of an additional copy of chromosome no. 21 (trisomy of 21st chromosome) is humans.

 

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