Abstract
BACKGROUND: The purpose of this study is to identify the mutations of the most common form of maturity-onset diabetes of the young (MODY), also known as MODY3, in diabetic patients suspected of MODY. This can recommend appropriate medical surveillance of at-risk family members of MODY based on the genetic cause. METHODS: We analyzed the clinical course of 19 patients from 12 unrelated Iranian families with diabetes features. The coding regions and intron-exon boundaries of the hepatocyte nuclear factor 1 alpha (HNF1A) gene were studied by polymerase chain reaction (PCR) and sanger sequencing. Also, the detected mutation was analyzed by bioinformatics tools. RESULTS: One novel frameshift insertion mutation (p.Glu11Argfs*12) was detected in one of the probands and seven other patients of her family with the heterozygote state. The mutation is located in the exon1 of the dimerization domain of the HNF1A gene. According to the In Silico analysis, the detected mutation is predicted as a pathogenic one. CONCLUSIONS: Differential diagnosis between MODY3 and other forms of diabetes can be considered a necessity in terms of overlapping symptoms of MODY3 with type1 or 2 diabetes. Molecular genetic testing can provide an accurate diagnosis for optimal management.