The effects of PER3 VNTR, 5-HTT-LPR, and 5-HTT-VNTR genotypes in terms of constituting liability to EDS were first determined with odds ratio (OR) and 95% confidence intervals (95% CI) by using ESS score ≥12 as a cut-off point. The gene discussed is PER3; the disease is Ehlers-Danlos syndrome.