Genotype information and individual health prediction

In general, Nutrigenomics research deals with complex diseases thought to result from the interplay between a collection of (for the most part not yet known) genetic traits and environmental and lifestyle factors, rather than with monogenic disorders caused by the mutation of a single gene. Even if all genetic traits contributing to a particular complex disease were known, genetic testing would only be able to indicate increased susceptibility, rather than the certainty of, future disease or response to dietary intervention. This is because many factors, including epistatic interactions between non-allele genes (e.g., suppression or potentiation of the effects of one gene variant by the concomitant presence of a particular variant of another gene) and present and past exposure to a collection of environmental factors, including diet and disease, might modify the phenotypic outcome of any given genotype, making it complex and difficult to interpret this kind of genotype information in terms of health benefit/risks to the individual.