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NEET2017ZoologyPrinciples of Inheritance and VariationActual

A disease caused by an autosomal primary non-disjunction is

Options

  1. ADown's syndrome
  2. BKlinefelter's syndrome
  3. CTurner's syndrome
  4. DSickle cell anemia

Correct answer

A. Down's syndrome

Step-by-step solution

Non-disjunction is the failure of homologous chromosomes to disjoin or separate and move away to opposite poles. Non-disjunction of the 21 st 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 21 st chromosome) is humans.

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