these methods can be difficult to apply in practice. Population substructure also can be used to advantage in genetic association studies. For example, populations that represent recent mixtures of geographically separated ancestral groups can exhibit longer-range linkage disequilibrium between susceptibility alleles and genetic markers than is the case for other populations. Genetic studies can use this admixture linkage disequilibrium to search for disease alleles with fewer markers than would be needed otherwise. Association studies also can take advantage of the contrasting experiences of racial or ethnic groups, including migrant groups, to search for interactions between particular alleles and environmental factors that might influence health. See also Full genome sequencing Inborn error of metabolism Predictive medicine References Further reading External links Genetics home reference The National Human Genome Research Institute hosts an information center The Phenomizer – A tool for clinical diagnostics in medical genetics. Phenomizer Cancer research