Which of the following genotype does not produce any sugar polymer on the surface of RBCs

Options

A. `I^(A)I^(A)`
B. `I^(B)i`
C. `I^(A)I^(B)`
D. `ii`

Answer

To solve the question regarding which genotype does not produce any sugar polymer on the surface of RBCs, we need to understand the ABO blood group system and the associated genotypes.

### Step-by-Step Solution:

1. **Understand the ABO Blood Group System**:
- The ABO blood group system consists of four main blood types: A, B, AB, and O. Each blood type is determined by the presence or absence of specific antigens (sugar polymers) on the surface of red blood cells (RBCs).

2. **Identify Antigens Associated with Each Blood Type**:
- **Blood Group A**: Has A antigens on the surface of RBCs.
- **Blood Group B**: Has B antigens on the surface of RBCs.
- **Blood Group AB**: Has both A and B antigens on the surface of RBCs.
- **Blood Group O**: Has no A or B antigens on the surface of RBCs.

3. **Genotypes Corresponding to Blood Types**:
- **Blood Group A**: Can be either homozygous (AA) or heterozygous (AO).
- **Blood Group B**: Can be either homozygous (BB) or heterozygous (BO).
- **Blood Group AB**: Is always heterozygous (AB).
- **Blood Group O**: Is always homozygous (OO).

4. **Determine Which Genotype Produces No Antigens**:
- Among the blood types, the O blood group (genotype OO) does not produce any sugar polymers (antigens) on the surface of RBCs.

5. **Conclusion**:
- Therefore, the genotype that does not produce any sugar polymer on the surface of RBCs is the homozygous O blood group (OO).

### Final Answer:
The genotype that does not produce any sugar polymer on the surface of RBCs is **O (homozygous, OO)**.

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