Mitochondrial DNA mutation in early-onset familial diabetes patients in Chifeng area

Objective To analyze the screening results of mitochondrial diabetes mellitus genes in early-onset familial diabetes in Chifeng,Inner Mongolia. Methods The clinical data and peripheral blood samples of 70 probands of early-onset type 2 diabetes mellitus in Chifeng Tumor Hospital,Inner Mongolia from August 2008 to September 2017 were collected.PCR amplification was used to screen the genes of the mitochondrial diabetes in probands,and the relationship between the gene site variations and clinical characteristics,complications and comorbidity was analyzed. Results Of the 70 cases,38 cases were male and 32 cases were female.Mitochondrial DNA mutation was found in 21 cases,with the mutation rate of 30% (21/70),and it was 28.94% (11/38) in male and 31.25% (10/32) in female,showing no significant difference (P=0.685).The mutations near nucleotide position 3243 located at 3141,3174,3203,3207,3317,3337,3338,3353,3395,3399,3435,3439,3524,3552,and simultaneously mutated positions were found in 3203 and 3552,3204 and 3353,3174 and 3317.The follow-up was lasted for 9 months.Of the 70 cases,1 case died and 11 cases were lost to follow-up;the other 58 cases were divided into gene mutation group (n=20) and non-mutation group (n=38).Dyslipidemia was found in 5% cases (1/20) in the gene mutation group,and 76% cases (29/38) in the non-mutation group,the difference was statistically significant (P=0.000).There was no significant difference in the other comorbidity between the two groups. Conclusion Mitochondrial DNA mutation is found In 30% of early-onset familial diabetes patients in Chifeng area.And our study has screend out the common mutation sites near nucleotide position 3243.