Table 1 Most plausible causes of discrepancies among different genetic association studies
Random errors | Confounders | Interactions |
|---|---|---|
• Bogus association due to multiple testing | • Phenotype is affected by variants at several genes (locus heterogeneity) | • Lack of consideration of gene-gene interactions |
• Small sample size | • Phenotype is affected by several variants at each locus (allele heterogeneity) | • Lack of consideration of gene-environment interactions |
• Inadequate choice of genetic variant | • Population stratification, especially on case-control studies |  |
• Genotyping errors | • Use of single markers instead of haplotypes |  |