Condition of a karyotype 2n +1, 2n-1 and 2n+2, 2n-2 are called:

Options

A. Aneuploidy
B. Polyploidy
C. Allopolyploidy
D. Monosomy

Answer

To solve the question regarding the conditions of karyotypes such as 2n + 1, 2n - 1, 2n + 2, and 2n - 2, we will break down the concepts step by step.

### Step-by-Step Solution:

1. **Understanding Karyotypes**:
- A karyotype is the number and appearance of chromosomes in the nucleus of a eukaryotic cell. The notation "2n" refers to the diploid number of chromosomes, which is the normal chromosome count for a species.

2. **Identifying the Conditions**:
- The conditions given are:
- **2n + 1**: This indicates one extra chromosome, leading to a total of 47 chromosomes. This condition is known as **trisomy**. An example is Down syndrome (trisomy 21).
- **2n - 1**: This indicates one missing chromosome, leading to a total of 45 chromosomes. This condition is known as **monosomy**. An example is Turner syndrome (monosomy X).
- **2n + 2**: This indicates two extra chromosomes, leading to a total of 48 chromosomes. This condition is also a form of **trisomy** but with an additional chromosome pair.
- **2n - 2**: This indicates two missing chromosomes, leading to a total of 44 chromosomes. This condition is known as **nullisomy**, where both homologous chromosomes of a pair are missing.

3. **Defining the Terms**:
- The conditions of karyotypes 2n + 1, 2n - 1, 2n + 2, and 2n - 2 are collectively referred to as **aneuploidy**. Aneuploidy is the presence of an abnormal number of chromosomes in a cell, which can result from nondisjunction during cell division.

4. **Conclusion**:
- Therefore, the answer to the question is that the conditions of karyotypes 2n + 1, 2n - 1, 2n + 2, and 2n - 2 are called **aneuploidy**.