Mendelian disorders can be traced in a family by

Options

A. pedigree analysis
B. cytological observaation
C. gene mapping
D. DNA fingerprinting

Answer

**Step-by-Step Solution:**

1. **Understanding Mendelian Disorders**: Mendelian disorders are genetic conditions that follow Mendel's laws of inheritance. They are caused by mutations in single genes and can be inherited in a predictable manner.

2. **Identifying the Options**: The options provided for tracing Mendelian disorders in a family are:
- Pedigree analysis
- Psychological observation
- Gene mapping
- DNA fingerprinting

3. **Evaluating Each Option**:
- **Pedigree Analysis**: This is a diagram that represents the familial relationships and the inheritance patterns of traits across generations. It helps in tracking the presence of Mendelian disorders within a family lineage.
- **Psychological Observation**: This method is not relevant for tracing genetic disorders as it focuses on behavioral aspects rather than genetic inheritance.
- **Gene Mapping**: This technique identifies the location of genes on chromosomes but does not directly trace the inheritance of disorders in families.
- **DNA Fingerprinting**: This is primarily used in forensic science to identify individuals based on their unique DNA patterns and is not used for tracing hereditary disorders.

4. **Conclusion**: Among the options, pedigree analysis is the most effective method for tracing Mendelian disorders in a family, as it provides a visual representation of how traits are passed down through generations.

5. **Final Answer**: Mendelian disorders can be traced in a family by **pedigree analysis**.

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