HLA-DRB1 and Achalasia: We found a significant increase in the frequency of the DRB1*14:54 allele in the achalasia group (G.F. = 0.0604) compared to that in the control group (G.F. = 0.0171, pC = 0.0200, OR = 3.7, 95% CI = 1.35–10.26).