Which term describes a trait controlled by two or more genes?

A polygenic trait is defined as a characteristic or trait that is influenced by two or more genes. This type of trait typically shows a range of phenotypes, which can create continuous variation among individuals, such as height, skin color, or weight in humans. Each contributing gene may have a small additive effect on the phenotype, leading to a wide spectrum of possible outcomes rather than a simple classification into distinct categories.

In contrast, the notion of multiple alleles pertains to a single gene that has more than two allele forms. This concept does not account for the influence of multiple genes on a single trait. Haploid and diploid traits refer to the number of sets of chromosomes in an organism’s cells—haploid cells have one complete set (like gametes), and diploid cells have two complete sets (like somatic cells)—but these terms do not specifically pertain to the interaction of multiple genes in controlling a trait. Therefore, polygenic trait is the accurate term to describe traits controlled by multiple genes.