Immunoglobulins, IgG and IgM, are routinely ordered by physicians for various diseases. However, for celiac disease, testing for IgA is preferred. When patients are IgA-competent, Tissue Transglutaminase (tTG) Antibody, IgA should be selected over Tissue Transglutaminase Antibody, IgG.
US Preventive Services Task Force, Bibbins-Domingo K, Grossman DC, et al. Screening for Celiac Disease: US Preventive Services Task Force Recommendation Statement. JAMA. 2017; 317 (12): 1252-1257.
Rubio-Tapia A, Hill ID, Kelly CP , et al. ACG clinical guidelines: diagnosis and management of celiac disease. Am J Gastroenterol. 2013; 108 (5): 656-76; quiz 677.