 Once a haplotype has been associated with a particular condition, other people can be screened for the presence of that haplotype and therefore gain some understanding of the risk groups they belong to. Although the test will not tell carriers of disease-linked SNPs whether they will develop the condition or not, it can nevertheless give them some information about their chances. Furthermore, even though the tag SNP itself might not be the genetic variation that causes or contributes to the variation in phenotype, it might be linked to so-called ‘causal SNPs’. Learning about SNPs associated with a condition or trait therefore can give the researcher clues as to which genes or regulatory DNA regions might be causally involved in the development of that condition. Findings from association studies can therefore in some cases contribute to the analysis of the condition itself.