Role of Fatty Acid Desaturase(s) (FADS) Polymorphisms in Determining the In Vivo Metabolism of Polyunsaturated Fatty Acids (PUFAs) in Botanical Oils in Humans.

The study will be a randomized, controlled, cross-over clinical trial of borage oil and soybean oil to determine whether the metabolism and/or impact of MC-PUFAs in botanical oil supplements are changed in relationship to specific genotypes in a SNP (rs174537) strongly associated with FADS1 activity and PUFA metabolism. Subjects previously genotyped at rs174537 will be given supplements and both blood PUFA (serum and erythrocyte membranes), urinary eicosanoids and eicosanoid release from whole blood (leukocyte generation) will be measured as biochemical determinants of genotype impact on supplement metabolism.

To evaluate the effect of genotype at the rs174537 locus on the metabolism of MC-PUFAs in borage and soybean oil to long chain polyunsaturated fatty acids (LC-PUFAs), including arachidonic acid, the investigators will utilize a double blind, randomized, crossover design. There will be three study groups based on the genotype of the healthy volunteer at rs174537. Individuals within each genotype will be consented and screened up to 8 weeks prior to randomization and the start of the intervention. Subjects will be randomized to begin with 4 weeks of either borage oil or soybean oil followed by an 8 week washout period, and then another 4 week period in which they take the second oil. Study visits will occur at 0, 2, and 4 weeks during each oil supplementation period, in addition to the consenting visit, for a total of 7 visits during the study.