In humans, red-green color blindness is determined by an X-linked recessive allele (a), whereas eye color is determined by an autosomal gene, where brown (B) is dominant over blue (b).If a blue-eyed mother with normal vision has a brown-eyed, color-blind son and a blue-eyed, color-blind daughter, what are the genotypes of both parents and children? A) The mother is BbX^AX^a, the father bbX^aY, the son bbX^aY, and the daughter BbX^aX^a. B) The mother is bbX^AX^a, the father BbX^aY, the son BbX^aY, and the daughter bbX^aX^a. C) The mother is BBX^AX^a, the father bbX^aY, the son BbX^aY, and the daughter BbX^aX^a. D) The mother is bbX^AX^a, the father BbX^aY, the son bbX^aY, and the daughter BbX^aX^a. E) It is impossible to determine from this information.

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The mother must be bb for blue eyes and X^AX^a for normal vision, as she has a color-blind son. The father must be Bb for brown eyes and X^aY for color blindness, as he passes the X^a to the daughter. The son is BbX^aY (brown-eyed, color-blind), and the daughter is bbX^aX^a (blue-eyed, color-blind).

In Humans, Red-Green Color Blindness Is Determined by an X-Linked