title: A search for non-chromosome 6 susceptibility loci contributing to rheumatoid arthritis.
abstract: We conducted a search for non-chromosome 6 genes that may increase risk for rheumatoid arthritis (RA). Our approach was to retrospectively ascertain three "extreme" subsamples from the North American Rheumatoid Arthritis Consortium. The three subsamples are: 1) RA cases who have two low-risk HLA-DRB1 alleles (N = 18), 2) RA cases who have two high-risk HLA-DRB1 alleles (N = 163), and 3) controls who have two low-risk HLA-DRB1 alleles (N = 652). We hypothesized that since Group 1's RA was likely due to non-HLA related risk factors, and because Group 3, by definition, is unaffected, comparing Group 1 with Group 2 and Group 1 with Group 3 would result in the identification of candidate susceptibility loci located outside of the MHC region. Accordingly, we restricted our search to the 21 non-chromosome 6 autosomes. The case-case comparison of Groups 1 and 2 resulted in the identification of 17 SNPs with allele frequencies that differed at p < 0.0001. The case-control comparison of Groups 1 and 3 identified 23 SNPs that differed in allele frequency at p < 0.0001. Eight of these SNPs (rs10498105, rs2398966, rs7664880, rs7447161, rs2793471, rs2611279, rs7967594, and rs742605) were common to both lists.
authors.affiliation: Department of Psychiatry, Washington University School of Medicine, 660 South Euclid, Campus Box 8134, St. Louis, Missouri 63110, USA.|Department of Genetics, Washington University School of Medicine, 660 South Euclid, St. Louis, Missouri 63110, USA.
authors.forename: Brian K
authors.initials: BK
authors.lastname: Suarez
authors.affiliation: Department of Medicine, Washington University School of Medicine, 660 South Euclid, St. Louis, Missouri 63110, USA.
authors.forename: Robert
authors.initials: R
authors.lastname: Culverhouse
authors.affiliation: Department of Psychiatry, Washington University School of Medicine, 660 South Euclid, Campus Box 8134, St. Louis, Missouri 63110, USA.
authors.forename: Carol H
authors.initials: CH
authors.lastname: Jin
authors.affiliation: Department of Psychiatry, Washington University School of Medicine, 660 South Euclid, Campus Box 8134, St. Louis, Missouri 63110, USA.
authors.forename: Anthony L
authors.initials: AL
authors.lastname: Hinrichs