Which one of the following blood group systems is determined by genes on the X chromosome

Options

A. Yt
B. ABO
C. Xg
D. MNSs

Explanation

To determine which blood group system is influenced by genes on the X chromosome, we will analyze the options provided:

1. **YT blood group system**
2. **ABO blood group system**
3. **XG blood group system**
4. **MNS blood group system**

### Step-by-Step Solution:

**Step 1: Understanding Blood Group Systems**
- Blood group systems are classifications of blood based on the presence or absence of specific antigens on the surface of red blood cells.

**Step 2: Identifying X-Linked Blood Group Systems**
- Some blood group systems are determined by genes located on the X chromosome. We need to identify which of the given options is X-linked.

**Step 3: Analyzing Each Option**
- **YT blood group system**: This system is not well-known to be X-linked.
- **ABO blood group system**: This system is determined by the I gene located on chromosome 9, not the X chromosome.
- **XG blood group system**: This system is known to be determined by a gene located on the X chromosome.
- **MNS blood group system**: This system is determined by genes on chromosome 4, not the X chromosome.

**Step 4: Conclusion**
- The blood group system that is determined by genes on the X chromosome is the **XG blood group system**.

### Final Answer:
The blood group system determined by genes on the X chromosome is the **XG blood group system**.