RESUMEN
OBJECTIVE: To explore MDOY1 gene mutations in pedigrees of early-onset familial type 2 diabetes. METHODS: We collected 100 early-onset type 2 diabetes pedigrees in Beijing, in which the probands were diagnosed with type 2 diabetes before the age of 40 years with at least one first-degree relative having such a diagnosis before the age of 45 years. PCR was employed to amplify all the exons and exon/intron splice sites of MDOY1 gene and the PCR products were sequenced to identify the DNA variants. RESULTS: Two DNA variants in the noncoding region including IVS1C +44A>T and IVS2 -5C>T were identified, and 3 mutations in the coding region we identified M49V, T130I, and S462S were found in these pedigrees. CONCLUSION: Currently no sufficient evidence has been obtained to identify the variation in or near MDOY1 genes as the major cause of early-onset type 2 diabetic in Chinese population.