Question

Albinism is inherited through a recessive allele (a). Juan has normal skin color. His Mom and Dad also have normal skin color. Juan marries Paige, who also has normal skin color. Surprisingly, their first child is an albino. What is everyone's genotype?

Juan _______ Juan's Mom __________ Juan's Dad _________

Answer 1

Juan, his parents, and Paige are all carriers of the recessive allele for albinism, which means their genotypes are heterozygous (Aa). This is because their albino child must have received one recessive allele from each parent, indicating they have the genotype aa for albinism.

Step-by-step explanation:

Given that albinism is an inherited recessive condition, Juan, his parents, and Paige must all be carriers of the recessive allele to have an albino child. Their genotypes would be as follows:

• Juan: Aa
• Juan's Mom: Aa
• Juan's Dad: Aa
• Paige: Aa

This is because for their child to exhibit albinism (aa), both parents must have contributed a recessive allele (a). Since Juan and Paige exhibit normal pigmentation, they must each possess one dominant allele (A) that masks the effect of the recessive allele (a). By using a Punnett square for a monohybrid cross, we can see that two heterozygous parents (Aa x Aa) have a 25% chance to have a child with albinism (aa).