Which genotype and phenotype is a result of aneouploidy in sex chromosomes ?

Options

A. 22 pairs + XXY male
B. 22+Xxfemale
C. 22pairs +XXXY female
D. 22 pairs +Y female

Answer

**Step-by-Step Solution:**

1. **Understanding Aneuploidy:**
- Aneuploidy refers to a condition where there is an abnormal number of chromosomes in a cell. Specifically, it involves the gain or loss of one or more chromosomes, but not a complete set. This can lead to various genetic disorders.

2. **Identifying the Relevant Chromosomes:**
- In humans, sex chromosomes determine the biological sex. Males typically have one X and one Y chromosome (XY), while females have two X chromosomes (XX).

3. **Analyzing the Given Options:**
- The question provides several genotypes:
- 22 pairs + XXY male
- 22 pairs + XX female
- 22 pairs + XY female
- 22 pairs + Y female

4. **Evaluating Each Option:**
- **Option 1: 22 pairs + XXY male**
- This indicates a male with an extra X chromosome. This is a classic example of aneuploidy (specifically Klinefelter syndrome).
- **Option 2: 22 pairs + XX female**
- This represents a normal female (no aneuploidy).
- **Option 3: 22 pairs + XY female**
- This is incorrect because XY indicates a male, not a female.
- **Option 4: 22 pairs + Y female**
- This is also incorrect, as the presence of a Y chromosome indicates a male.

5. **Conclusion:**
- The only genotype that results from aneuploidy in sex chromosomes is **22 pairs + XXY male**. The phenotype associated with this genotype is that of a male with Klinefelter syndrome, which may include features such as reduced fertility, breast tissue development, and taller stature.

**Final Answer:**
- The genotype resulting from aneuploidy in sex chromosomes is **XXY (Klinefelter syndrome)**, and the phenotype is that of a **male**.

---