We identified a peptide (celiac peptide: VVKGGSSSLGW) that was specifically recognized by serum IgA of 15 out of 22 (68%) individual patients with active disease on GCD and by serum IgA of only four of the same 22 patients on GFD, by both direct and competitive ELISA (Figure 1A). Here, CD79A is linked to glycogen storage disease VI.