The HLA genes are located on an autosome (chromosome 6). Autosomes are inherited in pairs - one from each parent; hence people carry two copies of each HLA gene. Inheriting one or more of the celiac-associated alleles (HLA-DQA1*05, HLA-DQB1*02, HLA-DQB1*0302) increases the risk of developing celiac disease. If an individual inherits both a celiac-associated HLA-DQA1 and a celiac-associated HLA-DQB1 allele, one or more of the celiac-associated heterodimers (DQ2 and DQ8) can form. It is these heterodimers that detect gluten and initiate the aberrant immune response.