Figure 2. Frequencies and disease effect sizes of imputed and genotyped HLA-DRB1 alleles.

We revisited our previous rheumatoid arthritis association studies using either typed SNPs [16] or HLA alleles [17]. After imputing HLA variants from the SNP-based dataset, (A) frequencies and (B) disease effect sizes of the imputed classical alleles of HLA-DRB1 were compared with those of genotyped classical alleles in the HLA-based dataset.