Plausibly, in connection with the data that IgA1 deposits predominate in the skin of DH sufferers, modification of the above ELISA tests to enable the determination of IgA1 subclass antibodies to tTG and npG would be even more valuable for differentiating IgA/neutrophil-mediated dermatoses. This evidence concerns the gene OPA1 and dermatitis herpetiformis, familial.