measured on the same phenotype as the original study. If another ethnic population is considered, the study is in essence no longer a replication study, since causal pathways and the relative contribution of polymorphism to these pathways may differ between populations. Failure to ‘replicate’ findings in a study of a different population compared to the original study will not allow any meaningful judgement on the validity of result in the original study, but can only provide information on the lack of effect in the second population.
