Which of the following could possibly increase genetic variation indirectly?

• A. Complete dominance at a single gene locus
• B. Replication of DNA without errors
• C. Epistasis between two genes affecting a trait
• D. Strict Mendelian inheritance with no gene interaction

Answer: (C)

Verified step by step guidance

1. Understand the concept of genetic variation: Genetic variation refers to differences in DNA sequences among individuals, which can lead to differences in traits.
2. Analyze each option in terms of its effect on genetic variation: For example, 'Complete dominance at a single gene locus' involves one allele masking another but does not create new variation; it only affects how existing variation is expressed.
3. Consider 'Replication of DNA without errors': This maintains the current genetic information without introducing new mutations, so it does not increase variation.
4. Examine 'Epistasis between two genes affecting a trait': Epistasis is an interaction where one gene affects the expression of another gene, which can create new phenotypic combinations and thus indirectly increase genetic variation in traits.
5. Evaluate 'Strict Mendelian inheritance with no gene interaction': This follows predictable inheritance patterns without interactions, so it does not increase variation beyond what is already present.