Red-green color blindness is X-linked recessive. A woman with normal color visio

Question

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 color-blind. Assume everyone in the family has a normal complement of chromosomes. Each of the next

three statements has an explanation for why none of the sons are color-blind. For each, state if it is possible or not possible, then give the reason for your choice.

i) None of the sons are color-blind because the mother does not carry the color-blindness allele.

ii) None of the sons are color-blind because none of them inherited the color-blindness allele from the mother.

iii) 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.

Explanation / Answer

None of the sons are color-blind because the mother does not carry the color-blindness allele. This is because the colorblindness is a X-linked recessive trait. If the sons to get the disease the mother must carry the allele and from mother the allele is passed to the sons. Option 1 is correct.

Related Questions

Navigate

• Browse (All)
• Browse R
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.