Which of the following disorder can occur with the same frequency in both sexes of humans?

Options

A. Turner's syndrome
B. Haemophilia
C. Klinefleter's syndrome
D. Phenylkentonuria

Answer

To solve the question regarding which disorder can occur with the same frequency in both sexes of humans, we will analyze each of the given options step by step.

### Step 1: Analyze Turner Syndrome
- Turner syndrome is a genetic disorder that occurs in females due to the absence of one X chromosome (45,X).
- This disorder only affects females, as males have XY chromosomes and do not develop Turner syndrome.

**Hint:** Turner syndrome is specific to females due to the absence of one X chromosome.

### Step 2: Analyze Hemophilia
- Hemophilia is an X-linked recessive disorder, primarily affecting males.
- Males have one X chromosome, so if they inherit the hemophilia gene, they will express the disorder. Females, having two X chromosomes, can be carriers without showing symptoms.

**Hint:** Hemophilia is more common in males because it is linked to the X chromosome.

### Step 3: Analyze Klinefelter Syndrome
- Klinefelter syndrome occurs in males who have an extra X chromosome (47,XXY).
- This disorder only affects males, as females do not have this chromosomal configuration.

**Hint:** Klinefelter syndrome is a male-specific disorder due to the presence of an extra X chromosome.

### Step 4: Analyze Phenylketonuria (PKU)
- Phenylketonuria is an autosomal recessive disorder that affects both males and females equally.
- It results from a deficiency in the enzyme phenylalanine hydroxylase, leading to an accumulation of phenylalanine in the blood.

**Hint:** PKU is an autosomal disorder, meaning it can affect both sexes equally.

### Conclusion
Based on the analysis of each disorder, the only disorder that can occur with the same frequency in both sexes is **Phenylketonuria (PKU)**.

**Final Answer:** Phenylketonuria (option 4) is the correct answer.