Barr body is missing in the female suffering from

Options

A. Huntington's disease
B. Tay sach's disease
C. Klinefelter's syndrome
D. Turner 's syndrome

Answer

### Step-by-Step Solution:

1. **Understanding Barr Body Formation**:
- Barr bodies are inactivated X chromosomes found in females. The number of Barr bodies can be calculated using the formula:
\[ \text{Number of Barr Bodies} = n - 1 \]
where \( n \) is the number of X chromosomes.

2. **Calculating Barr Bodies in Normal Individuals**:
- In a normal male (XY), there is 1 X chromosome:
\[ 1 - 1 = 0 \quad \text{(0 Barr bodies)} \]
- In a normal female (XX), there are 2 X chromosomes:
\[ 2 - 1 = 1 \quad \text{(1 Barr body)} \]

3. **Identifying Conditions with Missing Barr Bodies**:
- The question states that a female is missing a Barr body, which implies she has only one X chromosome. This condition is indicative of a chromosomal abnormality.

4. **Determining the Chromosomal Condition**:
- A female with only one X chromosome has a chromosomal complement of \( X_0 \) (monosomy). This condition is known as Turner’s syndrome.

5. **Characteristics of Turner’s Syndrome**:
- Turner’s syndrome is characterized by:
- 44 autosomes + 1 X chromosome (total 45 chromosomes).
- Sterility, underdeveloped secondary sexual characteristics, and other physical features.

6. **Exclusion of Other Conditions**:
- Other conditions mentioned (Hutchinson's disease, Tay-Sachs disease, Klinefelter's syndrome) do not relate to the absence of Barr bodies in females:
- Klinefelter's syndrome (XXY) would have 1 Barr body.

7. **Final Answer**:
- The female suffering from the absence of a Barr body is diagnosed with Turner’s syndrome.