Permanent neonatal diabetes due to a novel insulin signal peptide mutation
نویسندگان
چکیده
We report a rare case of permanent neonatal diabetes (PND) due to insulin (INS) gene mutation in a 51-month-old girl who presented with hyperglycemia in the neonatal period. Mutational analysis of KCNJ11 and INS was performed and this detected a novel heterozygous c.38T>G (p.Leu13Arg) INS de novo mutation. The non-conservative change substitutes the highly conserved L(13) residue within the hydrophobic core region of the preproinsulin signal peptide. Given the frequent tendency of heterozygous INS mutations to exhibit dominant negative disease pathogenesis, it is likely that the mutant preproinsulin perturbed the non-mutant counterpart progression and processing within the β-cells, and this resulted to a permanent form of congenital diabetes.
منابع مشابه
Genetic Susceptibility to Transient and Permanent Neonatal Diabetes Mellitus
Neonatal diabetes mellitus (NDM) is a rare kind of diabetes characterized by hyperglycemia and low levels of insulin. Clinically, it is categorized into two main types: transient NDM (TNDM) and permanent NDM (PNDM). These types are diagnosed based on duration of insulin dependence early in the disease. In TNDM, diabetes begins in the first few weeks of life with remission in a few months. Howev...
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