A patient comes to the clinic with a genetic disorder characterized by a webbed neck and the presence of rudimentary ovaries. This person most likely has

Options

A. two X and one Y sex chromosomes
B. only one sex chromosome which is X
C. three `21^(st)` chromosome
D. three X chromosomes

Answer

**Step-by-Step Solution:**

1. **Identify the Symptoms**: The patient presents with a webbed neck and rudimentary ovaries. These symptoms are critical in diagnosing the genetic disorder.

2. **Understand the Significance of Symptoms**:
- A webbed neck is often associated with certain genetic disorders, particularly Turner syndrome.
- Rudimentary ovaries indicate that the ovaries have not developed properly, which is a significant symptom in females with Turner syndrome.

3. **Consider the Genetic Background**:
- Turner syndrome is characterized by the presence of a single X chromosome (45, X0). This means that there is a total of 45 chromosomes instead of the usual 46, with one sex chromosome being absent.
- The absence of the second X chromosome leads to the development of the symptoms observed in Turner syndrome, including short stature, webbed neck, and underdeveloped ovaries.

4. **Eliminate Other Options**:
- **2X and 1Y chromosomes**: This condition is associated with Klinefelter syndrome, which affects males and does not present with rudimentary ovaries.
- **Three 21st chromosomes**: This indicates Down syndrome, which is an autosomal condition and does not relate to the symptoms described.
- **Three X chromosomes**: This condition is associated with Triple X syndrome, which does not typically present with the symptoms mentioned.

5. **Conclusion**: Based on the symptoms and genetic analysis, the patient most likely has Turner syndrome, characterized by the presence of one X chromosome and the absence of the second X chromosome (45, X0).

**Final Answer**: The patient most likely has Turner syndrome.

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