STK11 rs2075604 Polymorphism Is Associated with Metformin Efficacy in Chinese Type 2 Diabetes Mellitus

The Genetic Polymorphisms of rs161620 and rs2229611 in G6PC 3'UTR Are Associated With Metformin Efficacy in Chinese Type 2 Diabetes Mellitus

Metformin is a classical oral hypoglycemic drug, often recommended as the first-line therapy for type 2 diabetes mellitus (T2DM). Previous research has shown that the efficacy of metformin is associated with the genetic polymorphisms of patients. Considering the role of G6PC in gluconeogenesis and glycogenolysis, this study aims to investigate the association of G6PC rs161620 and rs2229611 with metformin efficacy in T2DM patients who take metformin only. According to the decrease of HbA1c, 116 T2DM patients receiving metformin monotherapy were divided into two groups: response group (the decrease of HbA1c by at least 1.5% after 3 months) and non-response group (the decrease of HbA1c < 1.5%). SNPscan technology was used to genotype. There were significant differences in rs161620 and rs2229611 presented in genotype frequency (p = 0.027 both) between the response group and the non-response group. According to the results of logistic analysis, the genetic polymorphisms of G6PC rs161620 or rs2229611 could influence the hypoglycemic effect of metformin in T2DM patients. We found that the decreasing values of PBG and HbA1c in G6PC rs161620 (C > A) or rs2229611 (T > C) mutants were significantly more than those in wild-type individuals, which means the more effective genotypes of metformin are CA/AA of rs161620 and TC/CC of rs2229611. This study suggested that the G6PC rs161620 and rs2229611 genetic polymorphisms were significantly associated with metformin efficacy in Chinese T2DM patients.

Single Nucleotide Polymorphism in the 3' Untranslated Region of PRKAA2 on Cardiometabolic Parameters in Type 2 Diabetes Mellitus Patients Who Received Metformin

Purpose

This study aimed to explore the association of rs857148 A>C as 3'UTR variants with blood pressure, HbA1c profile, and lipid profiles as cardiometabolic parameters among patients with T2DM receiving metformin.

Patients and Methods

This cross-sectional analytic research was conducted with 114 consecutively selected patients with T2DM. Polymerase chain reaction-restriction fragment length polymorphism was conducted to determine rs857148. A total of 108 patients fulfilled inclusion and exclusion criteria.

Results

Genotype distribution agreed with the Hardy Weinberg Equation for Equilibrium (p>0.05) but wildtype allele was found as the minor allele. Subjects with CC genotype and C allele had enhanced HbA1c levels (OR=7.12; 95% CI=1.05-48.26; p=0.04; OR=1.66; 95% CI=1.06-2.60; p=0.03, respectively). It was confirmed by dominant model whereas subjects with AA tended to have reduced HbA1c compared to AC+CC genotype (OR=0.15; 95% CI=0.02-0.97; p=0.047). AC genotype had significant correlation to total cholesterol (OR=1.05; 95% CI=1.01-1.10; p=0.03) compared to AA genotype.

Conclusion

We conclude that polymorphism of rs87148, specifically CC genotype and C allele, has a significant association with HbA1c and total cholesterol after considering oral hypoglycemia agent dose, age, gender, and combination therapy, compared to AA genotype. Future studies that involve a larger sample population and more rigorous selection criteria are required.

PRKAA2 variation and the clinical characteristics of patients newly diagnosed with type 2 diabetes mellitus in Yogyakarta, Indonesia

Background

Adenosine monophosphate (AMP)-activated protein kinase (AMPK; EC 2.7.11.31) enzymes play a pivotal role in cell metabolism. They are involved in type 2 diabetes mellitus (T2DM) pathogenesis. Genetic variation of PRKAA2 coding for the AMPK α2 catalytic subunit (AMPKα2) is reported to be associated with susceptibility for T2DM.

Objectives

To determine the association between PRKAA2 genetic variations (rs2796498, rs9803799, and rs2746342) with clinical characteristics in patients newly diagnosed with T2DM.

Methods

We performed a cross-sectional study including 166 T2DM patients from 10 primary health care centers in Yogyakarta, Indonesia. We measured fasting plasma glucose, hemoglobin A1c, serum creatinine, glomerular filtration rate, blood pressure, and body mass index as clinical characteristics. PRKAA2 genetic variations were determined by TaqMan SNP genotyping assay. Hardy-Weinberg equilibrium was calculated using χ2 tests.

Results

There was no difference in clinical characteristics for genotypes rs2796498, rs9803799, or rs2746342 (P > 0.05). No significant association was found between PRKAA2 genetic variations and any clinical feature observed. Further subgroup analysis adjusting for age, sex, and waist circumference did not detect any significant association of PRKAA2 genetic variations with clinical characteristics (P > 0.05).

Conclusion

PRKAA2 genetic variation is not associated with the clinical characteristics of Indonesian patients with newly diagnosed T2DM.

To the Editor

Ethn Dis. 2020;30(4):701-702; doi:10.18865/ed.30.4.701

A Protocol for the Study of Polymorphisms and Response to Metformin in Patients with Type 2 Diabetes in Trinidad

Background

Metformin is the drug of first choice in people newly diagnosed with type 2 diabetes. Most patients respond to metformin monotherapy, but many others remain uncontrolled even at maximal doses. Although non-adherence is a major contributor to non-response, genetic polymorphisms of organic cation transporters play an important role in clinical response. We hypothesize that genetic variants are partly responsible for non-response.

Objective

This study aims to determine the allele and genotype frequencies of three single nucleotide polymorphisms (SNPs; ATM rs11212617, SLC22A1 rs594709 and SLC47A1 rs2289669) most commonly associated with failure to respond to metformin.

Setting

Ten primary health care facilities in the North Central Regional Health Authority region of Trinidad.

Patients

The study population will include 216 patients with diabetes adherent to metformin monotherapy for at least three months.

Methods

Following a 12-hour overnight fast, blood samples will be taken to measure fasting insulin and HbA1c. DNA would be isolated and PCR will be used to determine the allele and genotype frequencies of these three SNPs in adherent diabetic patients. DNA samples will be stored for future sequencing of these three genes to determine whether other, possibly novel, mutations are associated with poor metformin response in Trinidad.

Clinical Significance

This study will highlight the prevalence of these polymorphisms in our population. Should an association be found between the polymorphisms tested and glycemic control in adherent patients on metformin monotherapy, this will have implications for further research on medication initiation in newly diagnosed patients with diabetes in Trinidad.