 Previous studies indicate that the variant status of detoxification proteins is different among Taiwanese and other ethnic groups. For example, in Taiwanese, the major SNPs of CYP2C9 are CYP2C92 430CT and CYP2C93 1075AC and their frequencies are different from that in Caucasians 11. The second example is that the frequency of the ATA7TAA allele in the promoter area of the UGT1A1 gene is substantially lower, while for the rate of variation within the coding region is much higher in Taiwanese than that in Caucasians 14.3 vs. 35.7- 41.5 and 29.3 vs. 0.1, respectively 12. The third example is that the frequency of 388AG of the OATP2 gene in Taiwanese 0.68 13 is in between that in European Americans 0.30 and African Americans 0.74 14. Therefore, the investigators hypothesize that, in Taiwanese the SNPs of detoxification proteins modulate the lipid-lowing effects of RVA and fenofibrate may be different from those for Caucasians. 