TGM2 and schizophrenia: TGM2 catalyzes the crosslinking of proteins by epsilon-gamma glutamyl lysine isopeptide bonds, appears to be involved in apoptosis and is the autoantigen implicated in celiac disease (gluten-sensitive enteropathy).61TGM2 SNPs and a haplotype showed nominal association (P~0.0004) to schizophrenia in a family-based study of 131 British family trios,62 though no association was found in a Chinese case–control study.63TGM2 has been reported (in a patent, US20070015152) to be upregulated in the brain (anterior cingulate cortex) of schizophrenia cases versus controls.