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A child with type O blood is born to a mother with type A blood. What is the genotype of the child? The mother? ‘what are the possible genotypes of the father?

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Final answer:

A child with type O blood has the genotype ii and can be born to parents with type A and B blood if they both carry the recessive allele 'i'. Type O blood cells lack A and B antigens and the person produces anti-A and anti-B antibodies. The father's genotype could be IAi, IBi, or ii.

Step-by-step explanation:

Understanding Blood Type Inheritance

The genotype of a child with type O blood is ii, consisting of two recessive alleles. A mother with type A blood can have either a homozygous (IAIA) or a heterozygous (IAi) genotype, but in this case, the mother must be heterozygous (IAi) to produce a child with type O blood. The possible genotypes of the father of a type O child could be IAi, IBi, ii, but not IAIA or IBIB as these would not provide the necessary 'i' allele.

Type O blood cells do not have A or B antigens on the surface of the red blood cells, while type B blood cells have B antigens, which type O blood lacks. People with type O blood produce anti-A and anti-B antibodies, which means they would react against blood cells that have either A or B antigens.

Parents with different blood types, including those with type A or B, can have offspring with various phenotypes because of the mixture of dominant (IA or IB) and recessive (i) alleles. For instance, a father with type A blood (AO genotype) and a mother with type B blood (BO genotype) can have offspring with blood types A, AB, B, or O.

An individual with type O blood (II genotype) can indeed be born to parents where one has type A and the other has type B, assuming each parent contributes one 'i' allele. In the case of two AB type parents, children can have A, B, or AB blood types, which is an example of codominance in inheritance.

User Ytropek
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Answer:

Genotype of the child is (oo)

The mother (Ao)

The father (oo/Ao/Bo)

Step-by-step explanation:

The woman is blood type A, but we know her genotype must be Ao (not AA) because she has a child with blood type O. That means the child got an o allele from each parent.

That's why dad must have at least one o. He could have three possible blood types (O, A, or B) with one genotype for each (oo, Ao, or Bo). The father cannot be blood type AB because then he couldn't give his child an o allele.

User Mosaaleb
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