Which of the following cannot be detected in a developing foetus by amniocentesis? (A) Down syndrome (B) Jaundice (C) Klinefelter syndrome (D) Sex of the foetus

Options

A. Down syndrome
B. Jaundice
C. Klinefelter syndrome
D. Sex of the foetus

Answer

To solve the question about which condition cannot be detected in a developing fetus by amniocentesis, we will analyze each option provided:

1. **Understanding Amniocentesis**:
- Amniocentesis is a medical procedure used to extract amniotic fluid from the amniotic sac surrounding a developing fetus. This procedure is typically performed between the 14th and 16th week of pregnancy.
- The extracted amniotic fluid contains fetal cells, which can be analyzed for genetic and chromosomal abnormalities.

2. **Analyzing Each Option**:
- **(A) Down Syndrome**: This is a chromosomal disorder caused by the presence of an extra chromosome 21 (trisomy 21). Amniocentesis can detect this condition by analyzing the fetal cells for chromosomal abnormalities.
- **(B) Jaundice**: Jaundice is a condition characterized by yellowing of the skin and eyes due to an excess of bilirubin in the blood. It is typically a metabolic disorder and does not involve chromosomal analysis. Therefore, it cannot be detected through amniocentesis.
- **(C) Klinefelter Syndrome**: This is a genetic condition caused by an extra X chromosome in males (XXY). Amniocentesis can identify this condition through chromosomal analysis.
- **(D) Sex of the Fetus**: The sex of the fetus can be determined through amniocentesis by analyzing the chromosomes present in the fetal cells (XX for female, XY for male).

3. **Conclusion**:
- The only condition that cannot be detected by amniocentesis is **(B) Jaundice**, as it is not a chromosomal or genetic disorder but rather a metabolic condition.

**Final Answer**: (B) Jaundice

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