Describe a characteristic that is influenced by many genes.

• A. Polygenetic traits
• B. Traits influenced by a single gene
• C. Polygenic traits
• D. Multigenic traits

Answer: (D)

Many traits are determined by the combined effect of several genes. Each gene adds a small amount to the overall phenotype, so their combined influence creates continuous variation across individuals rather than discrete categories. The standard term for this is polygenic traits, describing characteristics shaped by many genes. Multigenic is another way people describe the same idea, indicating multiple genes contribute to the trait. This additive effect across many genes explains why traits like height, skin color, or enzyme activity show a wide range of phenotypes rather than a single, fixed outcome. In contrast, traits influenced by a single gene tend to fall into distinct categories.