Britannica Sources used in this answer

How do genes and environmental factors work together in multifactorial diseases?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

BRCA2 tumor suppressor gene on chromosome 13 — human genetic disease Photomicrograph of the *BRCA2* tumor suppressor gene on chromosome 13 of the human genome. Inactivation of this growth-regulating gene is associated with a higher risk of developing breast cancer.

Multifactorial diseases are conditions that arise from the complex interplay between multiple genes and environmental factors. Rather than being caused by a single genetic mutation, these disorders result from the combined influence of several gene loci acting in concert with external elements like lifestyle, diet, and environmental exposure.123

In this process, an individual's genetic constitution dictates their susceptibility and response to environmental challenges. Conversely, environmental factors are often necessary for the manifestation of a disease; for example, a genetic predisposition to a condition may only result in clinical disease if triggered by specific environmental conditions. Because these factors are often intertwined, it is frequently impossible to isolate the separate contributions of nature and nurture in a single individual.34

Common conditions considered multifactorial include cancer, heart disease, diabetes, obesity, and hypertension. Understanding these interactions is essential for improving diagnostic, prognostic, and therapeutic strategies for these prevalent health issues.13