Which of the following statements about genetic variants is true?

• A. Genetic variants are always inherited in a dominant manner.
• B. Variants only occur in coding regions of the genome.
• C. All genetic variants result in observable phenotypic changes.
• D. Genetic variants can influence the expression of other genes through gene-gene interactions.

Answer: (D)

Verified step by step guidance

1. Understand the definition of genetic variants: Genetic variants are differences in the DNA sequence among individuals. These can occur anywhere in the genome, including both coding and non-coding regions.
2. Evaluate the inheritance patterns of genetic variants: Variants are not always inherited in a dominant manner; they can be dominant, recessive, co-dominant, or show other complex inheritance patterns.
3. Consider the location of variants: Variants can occur in coding regions (which directly affect protein sequences) as well as in non-coding regions (which can regulate gene expression).
4. Assess the phenotypic impact of variants: Not all genetic variants lead to observable phenotypic changes; some may be neutral or have effects only under certain environmental conditions.
5. Recognize gene-gene interactions (epistasis): Genetic variants can influence the expression of other genes through interactions, affecting phenotypes in complex ways beyond simple inheritance patterns.