HLA fine mapping
Multiple signals were identified in the HLA region according to GWAS;
therefore, we further discover the association between the HLA allele
and IgE. The HLA star allele with FDR adjusted p values less than 0.05
were shown in Table 3. The most significant signal, HLA-DQB1*03:03 (beta=0.15, SE=0.05, p = 3.70×10-14)
is associated with IgE under dominant genetic model. After stepwise
conditional analysis under the dominant model, no other signals remained
genome-wide significant (S Table 1 ). We further select two most
significant HLA genes, HLA-DQB1 and HLA-DQA1 to
conduct haplotype analysis. The haplotype HLA-DQA1*03:02 -
HLA-DQB1*03:03 with frequency 0.15 became more significant positively
associated with serum IgE (OR = 1.25, SE = 0.02, p-value =
8.88×10-16) compared with the most protective
haplotype (S Table 2) .