Question

A woman is married for the second time. Her first husband was ABO blood type A, and her child by that marriage was type O. Her new husband is type B and their child is type AB. What is the women’s ABO genotype and blood type?
A)${I^a},{\text{ }}{I^o}$ and blood type A
B)${I^a},{\text{ }}{I^o}$ and blood type AB
C)${I^b},{I^o}$ and blood type B
D)${I^o},{I^o}$ and blood type O.

Answer 1

ABO blood group is the major human blood group system. Blood group matching is a very crucial step during the process of organ transplantation.

Complete answer:
The ABO type of a person depends on the presence or absence of two genes, A and B. These genes determine the configuration of the red blood cell surface. A person who has two A genes or an A or an O gene has red blood cells of type A, whereas a person having two B genes or one B and one O gene has red blood cells of type B. If the presence of both A and B genes then his red blood cells will be of type AB. If a person has neither A not the B gene , the red cell types are of O type.

Now, according to the question,
Genotypes of the blood groups of the First husband are: IA I. And his child – ii
New husband: IB I and his child: IA IB

O positive is the most frequently occurring blood type and is found in approximately $37\%$ of the population. Whereas O negative is rare and found in $6\%$ of the population.

Hence, the correct answer is option (A)

Note: There are many types of blood typing systems but the most familiar and most accepted system is ABO and Rh systems. This system provides eight basic blood types. Generally, AB negative is considered to be the rarest blood type.