The effect of polymorphisms in the renin-angiotensin-aldosterone system on diabetic nephropathy risk

The genetic side of diabetic kidney disease: a review

BACKGROUND

Diabetic kidney disease (DKD) is one of the most common complications of diabetes, with approximately 30-40% of patients with type 1 diabetes mellitus and 20% of patients with type 2 diabetes mellitus eventually developing DKD. If DKD is not controlled in the early clinical stage and proteinuria develops, the disease will progress to end-stage renal disease. The pathogenesis of DKD remains largely unknown and is multifactorial, likely due to interactions between genetic and environmental factors. Familial clustering also supports a critical role of hereditary factors in DKD. The development of gene detection technology has promoted the exploration of DKD susceptibility genes in different cohorts of patients with diabetes. Identifying susceptibility genes can provide insights into the pathogenesis of DKD, as well as a basis for its clinical diagnosis and therapy.

RESULTS

Numerous candidate gene loci have been found to be associated with DKD, many of which play critical regulatory roles in the pathogenesis of this disease, including genes involved in glycol-metabolism, lipid metabolism, the renin-angiotensin-aldosterone system, inflammation and oxidative stress. In this review, we summarize the functions of several susceptibility genes involved in the development of DKD.

CONCLUSION

Based on our findings, we recommend that studying susceptibility gene polymorphisms can lead to a better understanding of the pathogenesis of DKD and could help prevent this disease or improve its outcomes.

The impact of angiotensin converting enzyme insertion/deletion gene polymorphism on diabetic kidney disease: A debatable issue

OBJECTIVE

The objective of this study was to evaluate the influence of ACE I/D gene polymorphisms on diabetic kidney disease (DKD) risk.

METHODS

All eligible investigations were identified, the number of various genotype in the case and control group were reviewed. The pooled analysis was performed using Stata software.

RESULTS

In overall subjects, 24,321 participants with 12,961 cases and 11,360 controls were included. the pooled analysis showed a significant link between D allele, DD or II genotype and DKD risk (D versus I: OR=1.316, 95% CI: 1.213-1.427, P=0.000; DD versus ID+II: OR=1.414, 95% CI: 1.253-1.595, P=0.000; II versus DD+ID: OR=0.750, 95% CI: 0.647-0.869, P=0.000). The subgroup pooled analysis showed that ACE I/D gene polymorphism was correlated with DKD both in Asian and in Chinese population. In addition, ACE I/D gene polymorphism was correlated with type 2 DKD (D versus I: OR=1.361, 95% CI: 1.243-1.490, P=0.000; DD versus ID+II: OR=1.503, 95% CI: 1.310-1.726, P=0.000; II versus DD+ID: OR=0.738, 95% CI: 0.626 -0.870, P=0.000). However, there was no obvious correlation in Caucasian subjects and type 1 diabetic patients.

CONCLUSION

ACE I/D polymorphisms were correlated with DKD in Asian and type 2 diabetic populations. ACE D allele/DD genotype might be a risk factor, while ACE II genotype might be a protective factor for DKD.

The impact of angiotensin converting enzyme insertion/deletion gene polymorphism on diabetic kidney disease: A debatable issue

OBJECTIVE

The objective of this study was to evaluate the influence of ACE I/D gene polymorphisms on diabetic kidney disease (DKD) risk.

METHODS

All eligible investigations were identified, the number of various genotype in the case and control group were reviewed. The pooled analysis was performed using Stata software.

RESULTS

In overall subjects, 24,321 participants with 12,961 cases and 11,360 controls were included. the pooled analysis showed a significant link between D allele, DD or II genotype and DKD risk (D versus I: OR=1.316, 95% CI: 1.213-1.427, P=0.000; DD versus ID+II: OR=1.414, 95% CI: 1.253-1.595, P=0.000; II versus DD+ID: OR=0.750, 95% CI: 0.647-0.869, P=0.000). The subgroup pooled analysis showed that ACE I/D gene polymorphism was correlated with DKD both in Asian and in Chinese population. In addition, ACE I/D gene polymorphism was correlated with type 2 DKD (D versus I: OR=1.361, 95% CI: 1.243-1.490, P=0.000; DD versus ID+II: OR=1.503, 95% CI: 1.310-1.726, P=0.000; II versus DD+ID: OR=0.738, 95% CI: 0.626 -0.870, P=0.000). However, there was no obvious correlation in Caucasian subjects and type 1 diabetic patients.

CONCLUSION

ACE I/D polymorphisms were correlated with DKD in Asian and type 2 diabetic populations. ACE D allele/DD genotype might be a risk factor, while ACE II genotype might be a protective factor for DKD.

Association between AGTR1 A1166C polymorphism and the susceptibility to diabetic nephropathy: Evidence from a meta-analysis

BACKGROUND

Diabetic nephropathy (DN) is a common complication in patients with diabetic mellitus (DM). Growing evidences have demonstrated that the polymorphisms of angiotensin II receptor type 1 (AGTR1) showed significant association with DN onset, but no consensus has been achieved yet. Therefore, we performed this meta-analysis to combine the findings of previous researches for a more comprehensive conclusion.

METHODS

Eligible publications were identified through electronic databases. The intensity of the correlation between AGTR1 A1166C polymorphism and DN susceptibility was evaluated through calculating pooled odds ratios (ORs) with their 95% confidence intervals (95% CIs). Heterogeneity among included studies was examined with Q test. When P-value less than .05, significant heterogeneity presented, random-effects model was used to calculate the pooled ORs, otherwise, the fixed-effects model was used. Stratification analyses were also performed based on ethnicity and the type of DM.

RESULTS

Seventeen eligible articles were finally included in the present meta-analysis. The analysis results showed that AGTR1 A1166C polymorphism was significantly related to increased risk of DN under CC versus AA (OR = 1.723, 95% CI = 1.123-2.644), CC + AC versus AA (OR = 1.179, 95% CI = 1.004-1.383), CC versus AA + AC (OR = 1.662, 95% CI = 1.112-2.486), and C versus A (OR = 1.208, 95% CI = 1.044-1.397) genetic models. Additionally, a similar result was also found in Asian and T2DM (type 2 diabetic mellitus) groups after subgroup analyses of ethnicity and DM type.

CONCLUSION

AGTR1 A1166C polymorphism may increase the susceptibility to DN, especially in Asians and T2DM population.

The Susceptibility Genes in Diabetic Nephropathy

Background

Diabetes mellitus (DM) poses a severe threat to global public health. Diabetic nephropathy (DN) is one of the most common complications of diabetes and the leading cause of end-stage renal disease (ESRD). Approximately 30-40% of DM patients in the world progress to ESRD, which emphasizes the effect of genetic factors on DN. Family clustering also supports the important role of hereditary factors in DN and ESRD. Therefore, a large number of genetic studies have been carried out to identify susceptibility genes in different diabetic cohorts. Extensive susceptibility genes of DN and ESRD have not been identified until recently.

Summary and Key Messages

Some of these associated genes function as pivotal regulators in the pathogenesis of DN, such as those related to glycometabolism and lipid metabolism. However, the functions of most of these genes remain unclear. In this article, we review several susceptibility genes according to their genetic functions to make it easier to determine their exact effect on DN and to provide a better understanding of the advancements from genetic studies. However, several challenges associated with investigating the genetic factors of DN still exist. For instance, it is difficult to determine whether these variants affect the expression of the protein they encode or other cytokines. More efforts should be made to determine how these genes influence the progression of DN. In addition, many results could not be replicated among races, suggesting that the association between genetic polymorphisms and DN is race-specific. Therefore, large, well-designed studies involving more relevant variables and ethnic groups and more relevant functional studies are urgently needed. These studies may be beneficial and retard the progression of DN by early intervention, especially for patients who carry certain risk alleles or genotypes.

Associations between angiotensinogen M235T polymorphisms and the risk of diabetic nephropathy: A meta-analysis

AIMS

The aim of the present study was to clarify the potential relationship of angiotensinogen (AGT) M235T polymorphism and diabetic nephropathy (DN) risk.

METHODS

Comprehensive electronic search in Pubmed, Web of Science, EBSCO, Embase, the Cochrane Library and China National Knowledge Infrastructure (CNKI) to find original articles about the association between AGT M235T polymorphism and DN risk published before 27 September 2017. Literature quality assessment was performed with the Newcastle-Ottawa Scale. Heterogeneity across studies was assessed using I² statistics. Random-effects model or Fixed-effects model was used to estimate the odds ratios (ORs) with 95% confidence intervals (CIs). Sensitivity analyses to assess the influence of individual studies on the pooled estimate. Publication bias was investigated using funnel plots and Egger's regression test. Analyses were performed by using Stata 15.0.

RESULTS

Overall, 20 eligible studies involving a total of 3822 cases and 3911 controls were included in our meta-analysis. The results showed that AGT M235T polymorphism significantly increased DN risk in recessive model (T/T versus M/T + M/M: OR = 1.35, 95%CI (1.07-1.69), I² = 63.8%, Z = 2.56, P = 0.010), homozygote model (T/T versus M/M: OR = 1.46, 95%CI (1.11-1.92), I² = 62.4%, Z = 2.69, P = 0.007) and allele model (T versus M: OR = 1.17, 95%CI (1.01-1.35), I² = 72.5%, Z = 2.14, P = 0.032); Subgroup analysis by ethnicity showed that AGT M235T polymorphism significantly increased DN risk in recessive model (T/T versus M/T + M/M: OR = 1.39, 95%CI (1.06-1.81), I² = 66.6%, Z = 2.42, P = 0.016), homozygote model (T/T versus M/M: OR = 1.47, 95%CI (1.08-2.01), I² = 67.7%, Z = 2.47, P = 0.013) and allele model (T versus M: OR = 1.18, 95%CI (1.02-1.37), I² = 69.4%, Z = 2.26, P = 0.024) in Caucasian DM population; Subgroup analysis by clinical subtype of DM also showed that AGT M235T polymorphism significantly increased DN risk in recessive model (T/T versus M/T + M/M: OR = 1.28, 95%CI (1.05-1.57), I² = 21.3%, Z = 2.40, P = 0.016), homozygote model (T/T versus M/M: OR = 1.41, 95%CI (1.04-1.92), I² = 30.2%, Z = 2.23, P = 0.026) and allele model (T versus M: OR = 1.14, 95%CI (1.03-1.28), I² = 35.5%, Z = 2.44, P = 0.015) in type 1 diabetes patients.

CONCLUSION

Our study showed that AGT M235T homozygous mutation significantly increase DN risk in Caucasian DM population and type 1 diabetes patients.

AT1R A1166C variants in patients with type 2 diabetes mellitus and diabetic nephropathy

Background: There are inconsistent reports related to the role of angiotensin II type 1 receptor (AT1R) on the risk of type 2 diabetes mellitus (T2DM) and its renal complications.

Objectives: To identify the association between AT1R A1166C variants with the risk of T2DM and also with diabetic nephropathy (DN). Patients and Methods: In a case-control study, the AT1R A1166C polymorphism was detected in 135 T2DM patients with and without DN and in 98 healthy subjects from Western Iran. The genotypes of AT1R A1166C polymorphism were detected using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method.

Results: The frequencies of AT1R A1166C genotypes and alleles were not significantly difference between patients with and without DN and controls. The frequencies of rare allele of 1166 C were 10%, 16.5%, 15.9% and 15.3% in micro-, macro- and normo-albuminuric patients and in healthy individuals, respectively ( P > 0.05). The systolic blood pressure and serum creatinine level in DN patients were significantly higher in carriers of AT1R CC compared to carriers of AT1R AA genotype. In the presence of uncontrolled hyperglycemia (HbA1c > 7.5%), there was a trend toward increased risk of macro-albuminuria in carriers of AC+CC genotype (OR=3.66, [95% CI: 0.81-16.58], P = 0.092).

Conclusions: Our study indicated the absence of an association between AT1R A1166C polymorphism with the risk of T2DM and DN. It seems in carriers of AT1R C allele systolic blood pressure and serum creatinine level to be higher compared to the A allele carriers.

Genome-wide association study of urinary albumin excretion rate in patients with type 1 diabetes

AIMS/HYPOTHESIS

An abnormal urinary albumin excretion rate (AER) is often the first clinically detectable manifestation of diabetic nephropathy. Our aim was to estimate the heritability and to detect genetic variation associated with elevated AER in patients with type 1 diabetes.

METHODS

The discovery phase genome-wide association study (GWAS) included 1,925 patients with type 1 diabetes and with data on 24 h AER. AER was analysed as a continuous trait and the analysis was stratified by the use of antihypertensive medication. Signals with a p value <10(-4) were followed up in 3,750 additional patients with type 1 diabetes from seven studies.

RESULTS

The narrow-sense heritability, captured with our genotyping platform, was estimated to explain 27.3% of the total AER variability, and 37.6% after adjustment for covariates. In the discovery stage, five single nucleotide polymorphisms in the GLRA3 gene were strongly associated with albuminuria (p < 5 × 10(-8)). In the replication group, a nominally significant association (p = 0.035) was observed between albuminuria and rs1564939 in GLRA3, but this was in the opposite direction. Sequencing of the surrounding genetic region in 48 Finnish and 48 UK individuals supported the possibility that population-specific rare variants contribute to the synthetic association observed at the common variants in GLRA3. The strongest replication (p = 0.026) was obtained for rs2410601 between the PSD3 and SH2D4A genes. Pathway analysis highlighted natural killer cell mediated immunity processes.

CONCLUSIONS/INTERPRETATION

This study suggests novel pathways and molecular mechanisms for the pathogenesis of albuminuria in type 1 diabetes.

Angiotensin-converting enzyme insertion/deletion polymorphism contributes high risk for chronic kidney disease in Asian male with hypertension--a meta-regression analysis of 98 observational studies

Background

Associations between angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphisms and chronic kidney disease (CKD) have been extensively studied, with most studies reporting that individuals with the D allele have a higher risk. Although some factors, such as ethnicity, may moderate the association between ACE I/D polymorphisms and CKD risk, gender-dependent effects on the CKD risk remain controversial.

Objectives

This study investigated the gender-dependent effects of ACE I/D polymorphisms on CKD risk.

Data sources

PubMed, the Cochrane library, and EMBASE were searched for studies published before January 2013.

Study eligibility criteria, participants, and interventions

Cross-sectional surveys and case–control studies analyzing ACE I/D polymorphisms and CKD were included. They were required to match the following criteria: age >18 years, absence of rare diseases, and Asian or Caucasian ethnicity.

Study appraisal and synthesis methods

The effect of carrying the D allele on CKD risk was assessed by meta-analysis and meta-regression using random-effects models.

Results

Ethnicity [odds ratio (OR): 1.24; 95% confidence interval (CI): 1.08–1.42] and hypertension (OR: 1.55; 95% CI: 1.04–2.32) had significant moderate effects on the association between ACE I/D polymorphisms and CKD risk, but they were not significant in the diabetic nephropathy subgroup. Males had higher OR for the association between ACE I/D polymorphisms and CKD risk than females in Asians but not Caucasians, regardless of adjustment for hypertension (p<0.05). In subgroup analyses, this result was significant in the nondiabetic nephropathy group. Compared with the I allele, the D allele had the highest risk (OR: 3.75; 95% CI: 1.84–7.65) for CKD in hypertensive Asian males.

Conclusions and implications of key findings

The ACE I/D polymorphisms may incur the highest risk for increasing CKD in hypertensive Asian males.

IGF2BP2 and IGF2 genetic effects in diabetes and diabetic nephropathy

OBJECTIVE

The IGF2BP2 gene is located on chromosome 3q27.2 within a region linked to type 1 diabetes (T1D), type 2 diabetes (T2D) and diabetic nephropathy (DN). Its protein functionally binds to 5'-UTR of the imprinting IGF2 gene. The present study aims to evaluate the IGF2BP2-IGF2 genetic effects in diabetes and DN.

MATERIALS AND METHODS

Three cohorts including T1D with and without DN (n=1139) of European descents from the GoKinD study, Swedish T1D with and without DN (n=303) and Czech control subjects without diabetes, T1D, T2D with and without DN (n=1418) were enrolled in TaqMan genotyping experiments for IGF2BP2 rs4402960 and IGF2 rs10770125. Igf2bp2 gene expression in kidney tissues of db/db and control mice at the ages of 5 and 26 weeks was examined with real time RT-PCR and Western blot.

RESULTS

An association of IGF2BP2 rs4402960 with T2D in the Czech population was replicated. This IGF2BP2 polymorphism (P=0.037, OR=0.69 95% CI 0.49-0.98) was found to be associated with DN in male not in female patients with T1D selected from the GoKinD study. In the analyses of combined the GoKinD, Czech and Swedish populations, the association between IGF2BP2 polymorphism and DN in male patients with T1D was still significant (P=0.030, OR=0.73, 95% CI 0.54-0.97). IGF2 rs10770125 was also associated with DN in male T1D patients of the GoKinD population (P=0.038, OR=0.67 95% CI 0.46-0.98). There might be a genetic interaction between IGF2BP2 and IGF2 (P=0.05). The Igf2bp2 gene expression levels were increased in the kidneys of db/db mice compared to controls at the age of 5weeks but not at 26 weeks.

CONCLUSIONS

The present study has replicated the association of IGF2BP2 rs4402960 with T2D in the Czech population and provided data suggesting that IGF2BP2 may have genetic interaction with IGF2 with a protective effect against DN in male patients with T1D.

Association of angiotensin I converting enzyme, angiotensin II type 1 receptor and angiotensin I converting enzyme 2 gene polymorphisms with the dyslipidemia in type 2 diabetic patients of Chinese Han origin

OBJECTIVE

To investigate whether the genetic polymorphisms in the angiotensin I converting enzyme (ACE) (insertion/ deletion, or I/D), angiotensin II type 1 receptor (AT1R) (rs5186), and ACE2 (rs2285666) could be associated with dyslipidemia in Type 2 diabetic (T2D) patients of Chinese Han origin.

DESIGN AND METHODS

The above 3 polymorphisms were genotyped in a total of 282 patients with T2D and dyslipidemia (Group A), 182 patients with T2D but without dyslipidemia (Group B), and 324 healthy controls. The association between a certain polymorphism and each group was assessed by an odds ratio (OR).

RESULTS

The D allele of the ACE (I/D) was significantly associated with the risk of T2D accompanying dyslipidemia between group A and controls [OR=1.37, 95% confidence interval (CI)=1.08-1.74; p=0.010], and significant association of the D allele with dyslipidemia was also observed in diabetic patients (OR=1.88, 95% CI=1.40-2.54; p<0.001). Furthermore, the ID genotype had a decreased risk of developing T2D without dyslipidemia as compared with controls (OR=0.52, 95% CI=0.32-0.82; p=0.0060). The distributions of the AT1R (rs5186) and ACE2 (rs2285666) genotypes and alleles did not differ between T2D patients with or without dyslipidemia and the controls.

CONCLUSIONS

This study demonstrates that the ACE (I/D) polymorphism is associated with T2D, regardless of the absence or presence of dyslipidemia. The polymorphisms in the AT1R (rs5186) and ACE2 (rs2285666) seem to play lesser roles in the development of T2D.

Association between genetic polymorphism of the angiotensin-converting enzyme and diabetic nephropathy: a meta-analysis comprising 26,580 subjects

Introduction: The effect of angiotensin-converting enzyme ( ACE) insertion/deletion (I/D) polymorphism on risk of diabetic nephropathy (DN) is still conflicting. The present meta-analysis was performed to evaluate the overall risk of this polymorphism associated with DN in different groups.

Materials and methods: A predefined search was performed on 14,108 DN cases and 12,472 controls from 63 published studies by searching electronic databases and reference lists of relevant articles.

Results: In this meta-analysis, we found a significant association between the ACE I/D polymorphism and the risk of DN for all genetic models (ID versus II: odds ratio [OR] = 1.12, 95% confidence interval [CI] 1.02–1.24; DD versus II: OR = 1.27, 95% CI 1.13–1.44; allele contrast: OR = 1.15, 95% CI 1.08–1.23; dominant model: OR = 1.18, 95% CI 1.07–1.31; and recessive model: OR = 1.18, 95% CI 1.08–1.30, respectively). In stratified analysis by ethnicity and DM type, we further found that the Asian group with type 2 diabetes mellitus (T2DM) showed a significant association for all genetic models (ID versus II: OR = 1.25, 95% CI 1.07–1.47; DD versus II: OR = 1.57, 95% CI 1.24–1.98; allele contrast: OR = 1.30, 95% CI 1.15–1.46; dominant model: OR = 1.37, 95% CI 1.10–1.69; and recessive model: OR = 1.34, 95% CI 1.15–1.56, respectively).

Conclusions: Our study suggested that the ACE I/D polymorphism may contribute to DN development, especially in the Asian group with T2DM.

A polymorphism in the angiotensin II type 1 receptor gene has different effects on the risk of diabetic nephropathy in men and women

BACKGROUND

The etiology of diabetic nephropathy depends partly on genetic factors. Elevated systemic and intraglomerular blood pressure and glomerular filtration rate, partly regulated by the renin-angiotensin system, increase the risk of diabetic nephropathy.

METHODS

The present case-control study investigated the association of the rs5186 polymorphism, in the angiotensin II type 1 receptor gene (AGTR1), with diabetic nephropathy. The study included 3561 patients with type 1 diabetes from Denmark, Finland, France and Sweden. Microalbuminuria was defined as albumin excretion rate (AER) ≥20 to <200 μg/min or albumin concentration ≥30 to <300 mg/l (n=707), macroalbuminuria was defined as AER≥200 μg/min or ≥300 mg/l (n=1546), and patients with renal replacement therapy were also included in this group. The controls had >15 years diabetes duration, AER <20 μg/min or <30 mg/l, and no antihypertensive treatment (n=1308).

RESULTS

AA genotype of the rs5186 polymorphism significantly increased the risk of diabetic nephropathy in male patients, OR=1.27 (95% CI=1.02-1.58), P=0.03, adjusted for age at diabetes onset, HbA1c, diabetes duration, smoking and country of origin. Among the women, there were no significant associations between rs5186 and diabetic nephropathy, OR=0.89 (0.71-1.11), P=0.30.

CONCLUSION

We conclude that the AGTR1 gene may be associated with increased risk of diabetic nephropathy in men with type 1 diabetes.

Investigation of ACE, ACE2 and AGTR1 genes for association with nephropathy in Type 1 diabetes mellitus

BACKGROUND

Polymorphisms in ACE and AGTR1 genes have been assessed in multiple studies for association with diabetic nephropathy; however, results are conflicting. The ACE2 gene has not been studied extensively for association with diabetic nephropathy.

METHODS

We investigated variants in ACE, ACE2 and AGTR1 for association with nephropathy in a case-control group (1467 participants with Type1 diabetes, case subjects n=718; control subjects n=749) of white descent with grandparents born in the British Isles. All recruited individuals were carefully phenotyped and genotyping was performed using Sequenom, Taqman and gel electrophoresis methods. The χ(2) -test for contingency tables was used to compare genotype and allele frequencies in case and control groups.

RESULTS

No departure from Hardy-Weinberg equilibrium was observed in cases or controls. Two variants within the ACE gene (rs4293, P(allelic) =0.02, P(genotypic) =0.008; rs4309, P(allelic) =0.02, P(genotypic) =0.01) were significantly associated with nephropathy at the 5% level. No variant remained statistically significant following adjustment for multiple comparisons. No single nucleotide polymorphisms in the ACE2 or AGTR1 genes were significantly associated with nephropathy when analysed either by genotype or allele frequencies.

CONCLUSIONS

Our independent case-control study provides no evidence that common variants in ACE, ACE2 and AGTR1 play a major role in genetic susceptibility to diabetic nephropathy in a white population with Type1 diabetes.

Genotypic interactions of renin-angiotensin system genes with diabetes type 2 in a Tunisian population

AIMS

To explore the role of genetic variants of angiotensinogen (AGT M235T), angiotensin-converting enzyme (ACE I/D), and angiotensin type 1 receptor (AT1R A1166C) as predictors of diabetes risk and to examine their combined effects on type 2 diabetes mellitus (T2DM) patients.

MAIN METHODS

One hundred and fourteen T2DM patients were compared to 175 healthy controls with similar age and sex.

KEY FINDINGS

The genotypic frequencies for all three genes alone were significantly associated with increased risk of developing diabetes. Logistic regression analysis of classic coronary risk factors and the genetic polymorphisms demonstrated that hypertension and ACE DD genotype were the most significant contributors to T2DM. For the renin-angiotensin system (RAS) genes, the risk of T2DM in individuals with one risk genotype was 1.9 (95%CI: 1.1-3.0, p=0.017) higher than those with zero risk genotype. Individuals who carried two risk genotypes had a 4.0 (95%CI 1.7-9.4, p=0.001) times higher risk of T2DM than those who did not carry any risk genotypes of the RAS genes. Most interestingly, the risk of T2DM for individuals with three risk genotypes was 26.2 (95%CI: 5.8-117.9, p<0.001) higher than those with zero risk genotype.

SIGNIFICANCE

The results of the present study imply that genotyping of renin-angiotensin system genes could become an important part of the clinical process of risk identification for T2DM in Tunisian population.