TGM2 and Autoimmunity: A prospective cohort study of newly diagnosed patients with GS has revealed a relationship between TG6 autoimmunity and brain atrophy in these patients.17,37 Hadjivassiliou et al reported the higher specificity and sensitivity of anti-tTG-6Ab in the identification of ataxic patients with or without enteropathy than anti-gliadin antibodies.