Genotypes of cytosolic low-molecular-weight protein-tyrosine-phosphatase correlate with age at onset of type 1 diabetes in a sex-specific manner

We investigated the possible role of cytosolic low-molecular-weight protein-tyrosine-phosphatase (cLMWPTP or acid phosphatase locus 1 [ACP1]) in the mediation of age at onset of type 1 diabetes. ACP1 is an enzyme involved in signal transduction of T-cell receptors, insulin, and other growth factor receptors. We studied acid phosphatase polymorphism in 189 consecutive children with type 1 diabetes admitted to the Pediatric Clinic of Sassari University (Sardinia) and in 86 adolescent patients with recently diagnosed type 1 diabetes from continental Italy. In both populations, females with medium-high activity acid phosphatase genotypes had onset of disease significantly earlier than males. The data suggest that acid phosphatase genotype affects the age of onset and probably also the sex ratio in type 1 diabetes. Sex hormones might modulate the susceptibility to autoimmune diseases, including type 1 diabetes, through the influence of signal transduction pathways involved in immune functions. Elucidation of the molecular basis for gender differences in the course and severity of type 1 diabetes could have important implications for treatment as well, because there might be gender-specific effects in the response to immunotherapy.