Select correct option w.r.t. trisomy aneuploidy

Options

A. Down's syndrome
B. Klinefeller's syndrome
C. turner's syndrome
D. All except (3)

Answer

To solve the question regarding trisomy aneuploidy, we need to understand the definitions and examples of trisomy and aneuploidy. Here’s a step-by-step breakdown of the solution:

### Step 1: Define Trisomy and Aneuploidy
- **Trisomy** refers to the presence of an extra chromosome, resulting in three copies of a particular chromosome instead of the normal two.
- **Aneuploidy** is a broader term that refers to any abnormal number of chromosomes, which can include having extra chromosomes (trisomy) or missing chromosomes (monosomy).

### Step 2: Identify Examples of Trisomy
- **Down Syndrome**: This condition is caused by trisomy of chromosome 21 (47 chromosomes total). It is a classic example of trisomy aneuploidy.
- **Klinefelter Syndrome**: This syndrome is characterized by the presence of an extra X chromosome in males (XXY), which also qualifies as a trisomy (47 chromosomes total).

### Step 3: Identify Non-Trisomy Example
- **Turner Syndrome**: This condition occurs when a female has only one X chromosome (XO), resulting in a total of 45 chromosomes. This is an example of monosomy, not trisomy.

### Step 4: Analyze the Options
- Based on the definitions and examples:
- Down Syndrome (Trisomy 21) - **Trisomy**
- Klinefelter Syndrome (XXY) - **Trisomy**
- Turner Syndrome (XO) - **Not Trisomy** (it is monosomy)

### Step 5: Select the Correct Option
- Since Down Syndrome and Klinefelter Syndrome are both examples of trisomy aneuploidy, while Turner Syndrome is not, the correct option would be the one that includes Down Syndrome and Klinefelter Syndrome but excludes Turner Syndrome.

### Final Answer
- The correct option is the one that states Down Syndrome and Klinefelter Syndrome are examples of trisomy aneuploidy, while Turner Syndrome is not.

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