NEETBiologyPrinciples of Inheritance and VariationMCQ+4 / −1
Down's syndrome is caused by an extra copy of
chromosome number 21. What percentage of
offspring produced by an affected mother and a
normal father would be affected by this disorder ?
- A50%
- B100%
- C75%
- D25%
View written solutionFree
Correct answer: A
Down’s syndrome is the example of autosomal aneuploidy. Here, an extra copy of chromosome 21 occurs. As it is an autosomal disease, the offsprings produced from affected mother and normal father should be 50%.
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