Multifactorial Genetic Conditions Multifactorial genetic conditions are disorders caused by the combined effects of multiple genes and environmental factors , rather than a single gene mutation . These conditions do not follow classic Mendelian inheritance patterns and instead result from complex gene–environment interactions . Factors such as lifestyle, nutrition, infections, stress, and exposure to toxins can significantly influence disease onset and severity in genetically susceptible individuals. Common examples include diabetes, cardiovascular diseases , neural tube defects, asthma, and many neuropsychiatric disorders. Understanding multifactorial inheritance is essential for risk prediction, preventive medicine, and personalized healthcare strategies. Multifactorial inheritance, polygenic traits, gene–environment interaction, complex diseases, genetic susceptibility, environmental risk factors, non-Mendelian inheritance, disease predisposition, polygenic risk score, precision ...