Red-green color blindness is X-linked recessive. A woman with normal color vision has a father who is red-green color blind. The woman has four sons, none of whom are colorblind. In this family there are no instances of chromosome loss or gain such as occurs due to nondisjunction in meiosis. Following are three explanations for why none of the sons are color blind. For each, state if color blindness is possible or not possible; then give the reason for your choice.
(a) Explanation 1: None of the sons are color blind because the mother does not carry the color-blindness allele.
(b) Explanation 2: None of the sons are color blind because none of them inherited the color-blindness allele from the mother.
(c) Explanation 3: None of the sons are color blind because the mother inactivated the X chromosome with the recessive color-blindness allele, and that is the one each son inherited.

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The Answer of Red-green color blindness is X-linked recessive. A woman with normal color vision has a father who is red-green color blind. The woman has four sons, none of whom are colorblind. In this family there are no instances of chromosome loss or gain such as occurs due to nondisjunction in meiosis. Following are three explanations for why none of the sons are color blind. For each, state if color blindness is possible or not possible; then give the reason for your choice.
(a) Explanation 1: None of the sons are color blind because the mother does not carry the color-blindness allele.
(b) Explanation 2: None of the sons are color blind because none of them inherited the color-blindness allele from the mother.
(c) Explanation 3: None of the sons are color blind because the mother inactivated the X chromosome with the recessive color-blindness allele, and that is the one each son inherited.

Red-Green Color Blindness Is X-Linked Recessive