HLA-C and ankylosing spondylitis: We also found multiple associations in rare alleles (MAF < 1%), including the novel HLA-B*57:31:02 in psoriasis (OR = 4.61, 95% CI: 3.22–6.59, p = 7.1 × 10−17, EAF = 0.06%) and HLA-C*02:178 in ankylosing spondylitis (OR = 5.33, 95% CI: 3.37–8.41, p = 7.75 × 10−13, EAF = 0.2%).