If two persons with 'AB' blood group marry and have suffieciently large number of children, these children could be classified as 'A' blood group: 'AB' blood group 'B' blood groUp in 1:2:1 ration. Modern technique of protein electrophoresis reveals presence of both 'A' and 'B' type proteins in 'AB' blood group individuals. This is an example of

Options

A. Partial dominance
B. Complete dominance
C. Codominance
D. Incomplete dominance

Answer

To solve the question regarding the inheritance of blood groups in children of two parents with 'AB' blood group, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Blood Group Genetics**:
- The ABO blood group system is determined by the presence of specific antigens on the surface of red blood cells. The alleles involved are:
- IA: A antigen
- IB: B antigen
- i: No antigen (O blood type)

2. **Parental Genotypes**:
- Both parents have the 'AB' blood group, which means their genotypes are IAIB.

3. **Possible Offspring Genotypes**:
- When two 'AB' individuals (IAIB x IAIB) have children, we can use a Punnett square to determine the possible genotypes of their offspring:
- Possible combinations are:
- IAIA (A blood group)
- IAIB (AB blood group)
- IBIA (AB blood group)
- IBIB (B blood group)
- This results in the following ratio:
- 1 (A) : 2 (AB) : 1 (B)

4. **Presence of Proteins**:
- The question states that modern techniques of protein electrophoresis reveal the presence of both 'A' and 'B' type proteins in individuals with 'AB' blood group. This indicates that both alleles are expressed.

5. **Identifying the Type of Inheritance**:
- The presence of both A and B proteins in the blood of AB individuals demonstrates that both alleles are expressed equally. This is a characteristic of **co-dominance**.

6. **Conclusion**:
- Therefore, the inheritance pattern observed in this scenario is an example of **co-dominance**.

### Final Answer:
The answer to the question is **co-dominance**.