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Question
About 8% of the human male population suffers from colour blindness, whereas only about 0.4% of the human female population suffers from this disease. Write an explanation to show how it is possible.
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Solution
Colour blindness is a sex-linked disorder and is caused by a recessive gene located on the X chromosome. The Y chromosome of male does not carry any gene for colour vision and the defect appears in the presence of a single recessive gene (XcY). As a result, colour blindness is more common in males (8%) as compared to females (0.4%).
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