We can only speculate on why PA is associated with a lower incidence of LADA only in individuals without genetic susceptibility to diabetes; the HLA-DRB1 and HLA-DQB1 genotypes are the main risk factors for β-cell autoimmunity and loss of β-cell function leading to type 1 diabetes (35). This evidence concerns the gene HLA-DQB1 and type 1 diabetes mellitus.