Genetically engineered insulin deffers from natural insulin in:

Options

A. absence of disulphide links
B. absence if C peotide chain
C. presence of oral and injectable from
D. none of these

Answer

To answer the question regarding how genetically engineered insulin differs from natural insulin, we can break down the information step by step:

### Step-by-Step Solution:

1. **Understanding Insulin Structure**:
- Insulin is a peptide hormone composed of two polypeptide chains known as the A chain and B chain. These chains are linked together by disulfide bridges.

2. **Natural Insulin Production**:
- In mammals, including humans, insulin is synthesized as a prohormone. This prohormone contains an additional segment known as the C-peptide, which is not present in the mature form of insulin.

3. **Genetically Engineered Insulin**:
- Genetically engineered insulin, such as that produced by the Eli Lilly company, is designed to be identical to human insulin but does not include the C-peptide. This means that the engineered form is a more direct version of the active hormone.

4. **Key Differences**:
- The primary difference between genetically engineered insulin and natural insulin is the absence of the C-peptide chain in the engineered version. The engineered insulin retains the A and B chains but lacks the C-peptide that is present in the prohormone form.

5. **Conclusion**:
- Therefore, the correct answer to the question is that genetically engineered insulin differs from natural insulin in the absence of the C-peptide chain.

### Final Answer:
The genetically engineered insulin differs from natural insulin in the absence of the C-peptide chain.