Why are gene results so complicated, and which genes predispose to gluten sensitivity/celiac sprue?
Gene tests for gluten sensitivity, and other immune reactions are HLA (human leukocyte antigen), specifically HLA-DQ, and even more specifically, HLA-DQB1. The nomenclature for reporting HLA gene results has evolved over the last two decades as technology has advanced. Even though the latest technology (and the one we employ at EnteroLab for gene testing) involves sophisticated molecular analysis of the DNA itself, the commonly used terminology for these genes in the celiac literature (lay and medical) reflects past, less specific, blood cell-based (serologic) antigenic methodology. Thus, we report this older “serologic” type (represented by the numbers 1-4, e.g., DQ1, DQ2, DQ3, or DQ4), in addition to the integeric subtypes of these oldest integeric types (DQ5 or DQ6 as subtypes of DQ1; and DQ7, DQ8, and DQ9 as subtypes of DQ3). The molecular nomenclature employs 4 or more integers accounting together for a molecular allele indicated by the formula 0yxx, where y is 2 for DQ2, 3 for an
