We have demonstrated that autoantibodies in gluten ataxia recognise a novel neuronal transglutaminase, TG6. TG6 is primarily expressed in neural tissue. We have postulated that anti-TG6 antibodies may prove to be a more sensitive and specific marker for gluten related neurological dysfunction. We investigated if TG6 antibodies can be the sole marker of gluten related neurological dysfunction. We tested 12 consecutive patients with sporadic idiopathic ataxia and no serological evidence of gluten sensitivity (negative for TG2, EMA and IgG and IgA anti-gliadin antibodies) for the presence of anti-TG6. All 12 patients underwent duodenal biopsy for routine histological examination as well as for evidence of IgA deposits against TG in the gut (a specific test for gluten sensitivity). Seven out of the 12 patients had antibodies against TG6. Four had both IgG and IgA, two had only IgG and one had only IgA antibodies. In 3 out of the 7 patients there was evidence of small bowel involvement (one had enteropathy, 2 had increased intraepithelial lymphocytes and all 3 had deposits against TG). These results suggest that anti-TG6 may be the only marker of gluten sensitivity in patients presenting with ataxia even in the presence of an enteropathy
