Salivary IgA can be stimulated by both the parasympathetic and sympathetic nerve system11,12 while α-amylase is majorly under sympathetic control13, suggesting changes in the IgA/α-amylase ratio could reflect alterations in the autonomic nervous system when progressing towards type 1 diabetes and/or neuropathy. The gene discussed is CD79A; the disease is type 1 diabetes mellitus.