The Mitochondrial Gene Mutations Analysis In 6 Cases Of Maternal Inherited Diabetes Patients

Objective:Mitochondrial diabetes mellitus is a special type of diabetes,which is caused by mitochondrial gene mutation.It is Belongs to a kind of cytogenetic defective disease.There are dozens of related mitochondrial gene mutations have been reported at home and abroad.The A3243 G mutation on the t RNALeu(UUR)genes is the most common pathogenic mutation in MDM,characterized by maternal inherited diabetes with neurogenic deafnessMIDD.Mitochondrial gene mutation has a high degree of polymorphism,so that individuals with a certain genetic susceptibility and clinical heterogeneity.That is to say the individuals carrying the same mutation showed different types and different degrees of clinical phenotype.In this study,mitochondrial gene analysis were performed in 6 cases patients with type 2 diabetes mellitus with maternally inherited.Method:4 cases deaf patients have a maternal inherited family history of type 2 diabetes and 2 cases of maternal inheritance without deafness in diabetes patients were collected in Shandong endocrine and metabolic disease hospital in this study.The subjects were tested for fasting blood glucose,glycosylated hemoglobin,insulin function test and so on.Physical examination included height,weight,and body mass index(BMI).Subjects was conducted a preliminary survey of the family history and gene extraction from peripheral blood.Polymerase chain reaction was used to direct sequencing of mitochondrial 3069-3842 fragment.There were mutations or significance performed whole mitochondrial DNA sequencing(except for the D loop region),to determine if there were mutations in the mitochondrial gene.Results:Of the 6 subjects in the mitochondrial 3069-3842 fragment,there was found a T3535 C synonymous mutation in 1 cases,which was frequent codons changed to rare codons,performed its case for the whole mitochondrial DNA sequence(in addition to the D loop area).In this study found a total of 6 missense mutations: G9053A、T10609C、C10920T、G13759A、G13928C、A15326G,2 non coding region mutations,and 13 synonymous mutations,2 of which T3535C、C3970T in the Mitochondrial NADH dehydrogenase ND1 gene resulted in codon changes.Conclusion:This study found 6 missense mutations in the mitochondria,the C10920T(P→L)mutations was associated with the clinical phenotype of patient with maternal inherited diabetes and deafness.