--while the transglutaminase tests are more specific for celiac--they are the tests that are most closely associated with villious damage to the small intestine--they do have about a 20% false negative rate . . .

Generally, in a celiac panel, the more sensitive but less specific anti-gliadin IgG and IgA tests will also be ordered, as well as an assay of total IgA, as a minority of people with congenitally low IgA may not get accurate results on tests of those antibody classes.