Which one is an interaction of genes

Options

A. Recessiveness
B. Dominance
C. Epistasis
D. Pleiotropy

Answer

To determine which option represents an interaction of genes, let's analyze the given options step by step.

### Step 1: Understand the Options
The options provided are:
1. Recessiveness
2. Dominance
3. Epistasis
4. Pleiotropy

### Step 2: Analyze Recessiveness and Dominance
- **Recessiveness**: This refers to a trait that is not expressed in the presence of a dominant allele. Recessive alleles do not interact with other alleles; they simply do not manifest when a dominant allele is present. Thus, recessiveness does not represent an interaction of genes.

- **Dominance**: This is a phenomenon where one allele masks the expression of another allele. While dominance involves the relationship between alleles, it does not involve interaction between different genes. Therefore, dominance is not considered an interaction of genes.

### Step 3: Analyze Epistasis
- **Epistasis**: This is a genetic interaction where one gene (non-allelic) can mask or modify the expression of another gene. In this case, the interaction between two genes is evident, as one gene's expression is altered by the presence of another gene. Therefore, epistasis is indeed an interaction of genes.

### Step 4: Analyze Pleiotropy
- **Pleiotropy**: This refers to a single gene influencing multiple phenotypic traits. While pleiotropy involves the effects of a single gene on various traits, it does not describe an interaction between different genes. Thus, pleiotropy is not an interaction of genes.

### Conclusion
Based on the analysis:
- The correct answer that represents an interaction of genes is **Epistasis**.

However, it is also noted that pleiotropy can involve interactions in a broader sense, but primarily, epistasis is the clear example of gene interaction.

### Final Answer
**Epistasis** is the interaction of genes.

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