Class 12th Biology 2016 Set2 Delhi Board Paper Solution
Question 22
Give an example of an autosomal recessive trait in humans. Explain its pattern of inheritance with the help of a cross.
Answer
Sickle Cell Anaemia is an autosomal recessive trait in humans. The genes responsible for this disease are located in autosomes. The disease being recessive the trait should be present in homozygous condition, for it to express.
People who carry a single copy of the gene are clinically normal but are carriers of the disease and can pass on the defective gene to their subsequent generation.
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