Subsequent analysis showed subjects with elevated levels of either tryptophanase or hpdBCA genes (third tertile [(T3]) had higher prevalence of ASCVD compared to those with low (first tertile [T1]) levels, even after adjustment for traditional CVD risk factors (odd ratio [OR] 95% CI for ASCVD, OR = 3.2 [1.9–5.8], P < 0.0001 and OR = 3.5 [1.9–6.4], P < 0.0001, respectively) (Fig. 7B and C). This evidence concerns the gene TDO2 and atherosclerosis.