Among the 33 markers identified, an eight-residue insertion at position 227-234 (rs28688207) in the cytoplasmic tail of HLA-DQβ1 emerged as the variant most closely related to achalasia, conferring an increased risk of developing the disease (p = 1.73 × 10−19) [[29], Figures 1 and 2]. This evidence concerns the gene HLA-DQB1 and Achalasia.