Predictors of GCA incidence in univariable analyses were HLA-DRB1*04 population allele frequency (P = 0.001, adjusted R2 = 0.51) and latitude (P = 0.004, adjusted R2 = 0.40), whereas HLA-DRB1*15 was non-significant. This evidence concerns the gene HLA-DRB1 and temporal arteritis.