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A list of disorders are given below .  Pick the odd one out and give reasons. A) Colour blindness   B) Hemophilia   C) Night blindness   D) Albinism   E) Sickle cell anemia

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Well, its a tough pick, but I am going with night blindness, answer choice "C", as the odd one out.  night blindness is a condition where a person has normal vision in strong sunlight, or under brightly lit conditions, and virtually no vision in dimly lit conditions.  This condition is facilitated by a lack of vitamin A in the diet, which nurtures the rods and cones in the interior of the eye, which are the receptors of incoming light.  The other diseases are all recessive-linked genetic diseases that are inherited by an individual from both his/her mother and father.  To have this type of disease expressed in a person's phenotype, a recessive gene must be inherited from both the father and the mother.  When both recessive alleles are present on a gene, the recessive trait linked to that allele is expressed as part of the persons phenotypic makeup, such as hemophilia, or sickle-cell anemia.

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