HLA-DPB1 and Achalasia: Subsequently, using molecular biology techniques, other results showed an association between the achalasia and the allele HLA-DQA1*0101 and two HLA-DQαβ heterodimers [25], DQB1*0602 [26], DQA1*0103 and DQB1*0603 [27], HLA-DP and HLA-DR [28].