Definition
A condition or trait resulting from the combined action of more than one gene.
Use in clinical context
A common misconception is that single genes exist for specific traits, such as height or eye colour. In fact, the majority of traits, including many health disorders, are determined by multiple genes, often combined with environmental factors. When a condition requires multiple genetic factors to manifest, it is termed a polygenic condition.
Many health disorders, such as heart disease and diabetes, are thought to be caused by the interplay of multiple genetic factors, so are polygenic. Most polygenic conditions are also influenced by environmental factors, and these should be considered when assessing an individual’s chance of developing a particular condition.
