[1] Univ Wisconsin, Vet Adm Hosp, Dept Med, Madison, WI 53705 USA
[2] Univ Wisconsin, Wisconsin Reg Primate Res Ctr, Madison, WI 53705 USA
[3] Univ Wisconsin, Dept Genet & Med Genet, Madison, WI 53705 USA
[4] Univ Wisconsin, Mol & Environm Toxicol Ctr, Madison, WI 53705 USA
[5] Univ Alabama, Dept Biostat, Sect Stat Genet, Birmingham, AL 35294 USA
[6] Univ Alabama, Clin Nutr Res Ctr, Birmingham, AL 35294 USA