Fig. 1From: Association of HLA-DRB1 amino acid residues with giant cell arteritis: genetic association study, meta-analysis and geo-epidemiological investigationGiant cell arteritis (GCA) incidence in relation to population HLA-DRB1 allele frequencies (a) and to latitude (b). Significance levels from a global test of difference in distribution of amino acid frequencies between cases and controls at specific positions (c)Back to article page