Study On The Correlation Between Polymorphism Of Adiponectin Gene And Type 2 Diabetes In Bai Nationality Groups

ObjectiveAn adipocyte-derived cytokine, adiponectin, is a member of the collagen superfamily. It can affect the metabolism of glucose and fat, and thus is associated with obesity, insulin resistance and type 2 diabetes. The frequencies of the T45G polymorphism in exon 2 of adiponectin gene (APM1) are different among variant race. Whether the polymorphism is associated with obesity, insulin resistance and type 2 diabetes is uncertain. In China, similar studies have been done in Han nationality. The aim of our experiment is to investigate the correlation between the T45G polymorphism of APM1 and type 2 diabetes in Bai nationality groups who reside in Dali area and to find out if the genotype distribution differs between Bai nationality and Han nationality. In addition, we observe if BMI, fasting blood glucose and blood lipid levels differ among populations in variant regions and ethnicities, and then we analyze the .causation of the result. MethodsAccording to the diagnostic criteria of ADA in 1997, we selected 40 subjects with T2DM of Bai nationality, 30 subjects with T2DM of Han nationality in Dali area and 92 T2DM patients of Bai nationality in Tianjin, as well as 30 non-diabetic subjects of Bai nationality in Dali and 122 non-diabetic subjects of Han nationality in Tianjin. Blood samples and correlative clinical data were collected. Genomic DNA was extracted from peripheral blood leucocytes of the participants. We screened the T45G polymorphism by means of PCR-RFLP in all subjects and identified the mutation by directly sequenced the PCR production. Then we compared the frequencies of genotype and allele as well as BMI, fasting blood glucose and blood lipid levels among variant groups.Results1. We screened 16 heteromutation and 3 homomutation from 40 diabetic subjects of Bai nationality. In the control group of Bai nationality, there were 10 heteromutation and 2 homomutation.There was no difference of the mutation frequency between the diabetic subjects and the non-diabetic subjects.2. In the diabetic group of Bai nationality, the BMI, FBG, PBG, TG, TC, LDL-C, HDL-C, FINS and HOMA-IR have no difference among diversified genotypes.3. In the control group of Bai nationality, the BMI, FBG, TG, TC, LDL-C and HDL-C levels have no difference among diversified genotypes.4. Among the non-diabetic subjects of Han nationality in Tianjin, the T—>G mutation frequency is 47.5%(data from a former study in Tianjin). Compared with that of Bai nationality, there was no statistical difference between them.5. The non-diabetic subjects of Han nationality in Tianjin have a significant higher average BMI and LDL-C level than the non-diabetic subjects of Bai nationality groups(P=0.000 and 0.005,respectively). Compared with T2DM patients of Bai nationality, Han population with type 2 diabetes in Tianjin has a significant higher BMI (P=0.006)and significant lower FBG and LDL-C levels(P=0.000). Conclusion1. Our study suggests that among Bai nationality in Dali area the SNP45 of APM1 is not associated with the risk of developing type 2 diabetes.2. For Bai nationality groups in Dali area the SNP45 of APM1 has no significant effects on BMI, FBG, TG, TC, LDL-C and HDL-C levels.3. We did not detect significant differences in genotype or allele frequencies for the SNP45 between Han nationality and Bai nationality.4. The non-diabetic subjects of Han nationality in Tianjin have a significant higher average BMI and LDL-C level than the non-diabetic subjects of Bai nationality groups and we consider the causation includes the difference of living style, living clime and ethnicity. Yet the APM1T45G doesn't attribute to it.5. Compared with T2DM patients of Bai nationality, Han population with type 2 diabetes in Tianjin has a significant higher BMI (P=0.006)and significant lower FBG and LDI^C levels(P=0.000), and the causation includes the difference of living style, living clime and iatrical level.