Association between 28 single nucleotide polymorphisms and type 2 diabetes mellitus in the Kazakh population: a case-control study

Exploring the rare variants associated with Type 2 Diabetes Mellitus in Indian population and its disease-drug association studies: an in-silico approach

The diversified eating habits and religious culture of Indian population may be one of the reasons they largely contribute to the global diabetes burden. In the present investigation, an in-silico approach was carried out to explore hub genes in the Indian population with Type 2 Diabetes Mellitus (T2DM) that are scantily reported in the GWAS catalogue and probable potential anti-diabetic drugs from plants. This computational approach unwrapped LEP (leptin) as the hub gene among 170 genes analyzed with 14 non-synonymous single nucleotide polymorphisms (nsSNPs) with MAF < 0.01. The mutation of the LEP gene leads to a decrease in leptin concentration, which increases the risk of obesity and T2DM. According to the DUET webserver, 11 of 14 mutations examined were found to destabilize the LEP protein. Among 14, four barely reported LEP variants rs781301976 (I45N), rs776443424 (S52F), rs200915360 (D76Y), and rs1191666811 (D162N) were unzipped to be associated with T2DM, which may be the probable potential drug targets. The virtual screening revealed Vescalagin as having the highest binding energy among 336 natural compounds. Molecular docking of Vescalagin depicted higher binding energy (-9.0 kcal/mol) against mutated LEP [rs200915360 (D76Y)] compared to wild (-8.9 kcal/mol) and LEP-Metformin complexes. The trajectory analysis of MD simulations revealed that Vescalagin was more effective than Metformin in stabilizing the system. The present study suggests that the associations of the investigated nsSNPs in LEP [rs200915360 (D76Y)] and others can be key factors in the predominant role of T2DM morbidity in the Indian population that can be used as potential markers and drug targets for T2DM therapeutics.Communicated by Ramaswamy H. Sarma.

Mechanisms and risk factors of metabolic syndrome in children and adolescents

Metabolic syndrome (MetS) is a complex disorder characterized by abdominal obesity, elevated blood pressure, hyperlipidemia, and elevated fasting blood glucose levels. The diagnostic criteria for MetS in adults are well-established, but there is currently no consensus on the definition in children and adolescents. The etiology of MetS is believed to involve a complex interplay between genetic predisposition and environmental factors. While genetic predisposition explains only a small part of MetS pathogenesis, modifiable environmental risk factors play a significant role. Factors such as maternal weight during pregnancy, children's lifestyle, sedentariness, high-fat diet, fructose and branched-chain amino acid consumption, vitamin D deficiency, and sleep disturbances contribute to the development of MetS. Early identification and treatment of MetS in children and adolescents is crucial to prevent the development of chronic diseases later in life. In this review we discuss the latest research on factors contributing to the pathogenesis of MetS in children, focusing on non-modifiable and modifiable risk factors, including genetics, dysbiosis and chronic low-grade inflammation.

Genotype-based precision nutrition strategies for the prediction and clinical management of type 2 diabetes mellitus

Globally, type 2 diabetes mellitus (T2DM) is one of the most common metabolic disorders. T2DM physiopathology is influenced by complex interrelationships between genetic, metabolic and lifestyle factors (including diet), which differ between populations and geographic regions. In fact, excessive consumptions of high fat/high sugar foods generally increase the risk of developing T2DM, whereas habitual intakes of plant-based healthy diets usually exert a protective effect. Moreover, genomic studies have allowed the characterization of sequence DNA variants across the human genome, some of which may affect gene expression and protein functions relevant for glucose homeostasis. This comprehensive literature review covers the impact of gene-diet interactions on T2DM susceptibility and disease progression, some of which have demonstrated a value as biomarkers of personal responses to certain nutritional interventions. Also, novel genotype-based dietary strategies have been developed for improving T2DM control in comparison to general lifestyle recommendations. Furthermore, progresses in other omics areas (epigenomics, metagenomics, proteomics, and metabolomics) are improving current understanding of genetic insights in T2DM clinical outcomes. Although more investigation is still needed, the analysis of the genetic make-up may help to decipher new paradigms in the pathophysiology of T2DM as well as offer further opportunities to personalize the screening, prevention, diagnosis, management, and prognosis of T2DM through precision nutrition.

mtDNA Single-Nucleotide Variants Associated with Type 2 Diabetes

Type 2 diabetes (T2D) is a chronic systemic disease with a complex etiology, characterized by insulin resistance and mitochondrial dysfunction in various cell tissues. To explore this relationship, we conducted a secondary analysis of complete mtDNA sequences from 1261 T2D patients and 1105 control individuals. Our findings revealed significant associations between certain single-nucleotide polymorphisms (SNPs) and T2D. Notably, the variants m.1438A>G (rs2001030) (controls: 32 [27.6%], T2D: 84 [72.4%]; OR: 2.46; 95%CI: 1.64-3.78; p < 0.001), m.14766C>T (rs193302980) (controls: 498 [36.9%], T2D: 853 [63.1%]; OR: 2.57, 95%CI: 2.18-3.04, p < 0.001), and m.16519T>C (rs3937033) (controls: 363 [43.4%], T2D: 474 [56.6%]; OR: 1.24, 95%CI: 1.05-1.47, p = 0.012) were significantly associated with the likelihood of developing diabetes. The variant m.16189T>C (rs28693675), which has been previously documented in several studies across diverse populations, showed no association with T2D in our analysis (controls: 148 [13.39] T2D: 171 [13.56%]; OR: 1.03; 95%CI: 0.815-1.31; p = 0.83). These results provide evidence suggesting a link between specific mtDNA polymorphisms and T2D, possibly related to association rules, topological patterns, and three-dimensional conformations associated with regions where changes occur, rather than specific point mutations in the sequence.

Metformin alleviates the cognitive impairment induced by benzo[a]pyrene via glucolipid metabolism regulated by FTO/FoxO6 pathway in mice

Benzo[a]pyrene (B[a]P) is neurotoxic; however, the mechanism and prevention are still unclear. In this study, we assessed the intervention effect of metformin (MET) on cognitive dysfunction in mice induced by B[a]P from the perspective of glucolipid metabolism. Forty-two male healthy ICR mice were randomly categorized into 6 groups and were gavaged with B[a]P (0, 2.5, 5, or 10 mg/kg), 45 times for 90 days. The controls were gavaged with edible peanut oil, and the intervention groups were co-treated with B[a]P (10 mg/kg) and MET (200 or 300 mg/kg). We assessed the cognitive function of mice, observed the pathomorphological and ultrastructural changes, and detected neuronal apoptosis and glucolipid metabolism. Results showed that B[a]P dose-dependently induced cognitive impairment, neuronal damage, glucolipid metabolism disorder in mice, and enhanced proteins of fat mass and obesity-associated protein (FTO) and forkhead box protein O6 (FoxO6) in the cerebral cortex and liver, which were alleviated by the MET intervention. The findings indicated the critical role of glucolipid metabolism disorder in the cognitive impairment in mice caused by B[a]P and the prevention of MET against B[a]P neurotoxicity by regulating glucolipid metabolism via restraining FTO/FoxO6 pathway. The finding provides a scientific basis for the neurotoxicity and prevention strategies of B[a]P.

Fatty Acid Profile and Genetic Variants of Proteins Involved in Fatty Acid Metabolism Could Be Considered as Disease Predictor

Circulating fatty acids (FA) have an endogenous or exogenous origin and are metabolized under the effect of many enzymes. They play crucial roles in many mechanisms: cell signaling, modulation of gene expression, etc., which leads to the hypothesis that their perturbation could be the cause of disease development. FA in erythrocytes and plasma rather than dietary FA could be used as a biomarker for many diseases. Cardiovascular disease was associated with elevated trans FA and decreased DHA and EPA. Increased arachidonic acid and decreased Docosahexaenoic Acids (DHA) were associated with Alzheimer's disease. Low Arachidonic acid and DHA are associated with neonatal morbidities and mortality. Decreased saturated fatty acids (SFA), increased monounsaturated FA (MUFA) and polyunsaturated FA (PUFA) (C18:2 n-6 and C20:3 n-6) are associated with cancer. Additionally, genetic polymorphisms in genes coding for enzymes implicated in FA metabolism are associated with disease development. FA desaturase (FADS1 and FADS2) polymorphisms are associated with Alzheimer's disease, Acute Coronary Syndrome, Autism spectrum disorder and obesity. Polymorphisms in FA elongase (ELOVL2) are associated with Alzheimer's disease, Autism spectrum disorder and obesity. FA-binding protein polymorphism is associated with dyslipidemia, type 2 diabetes, metabolic syndrome, obesity, hypertension, non-alcoholic fatty liver disease, peripheral atherosclerosis combined with type 2 diabetes and polycystic ovary syndrome. Acetyl-coenzyme A carboxylase polymorphisms are associated with diabetes, obesity and diabetic nephropathy. FA profile and genetic variants of proteins implicated in FA metabolism could be considered as disease biomarkers and may help with the prevention and management of diseases.

Insulin resistance in Alzheimer's disease: The genetics and metabolomics links

Alzheimer's disease (AD) is a neurodegenerative disease with significant socioeconomic burden worldwide. Although genetics and environmental factors play a role, AD is highly associated with insulin resistance (IR) disorders such as metabolic syndrome (MS), obesity, and type two diabetes mellitus (T2DM). These findings highlight a shared pathogenesis. The use of metabolomics as a downstream systems' biology (omics) approach can help to identify these shared metabolic traits and assist in the early identification of at-risk groups and potentially guide therapy. Targeting the shared AD-IR metabolic trait with lifestyle interventions and pharmacological treatments may offer promising AD therapeutic approach. In this narrative review, we reviewed the literature on the AD-IR pathogenic link, the shared genetics and metabolomics biomarkers between AD and IR disorders, as well as the lifestyle interventions and pharmacological treatments which target this pathogenic link.

Insulin receptor substrate-1 gene polymorphism and lipid panel data in type 2 diabetic patients with comorbid obesity and/or essential hypertension

Objective. The hallmarks of type 2 diabetes mellitus (T2DM) are insulin resistance (IR) and insulin receptor substrate (IRS) proteins essential for the insulin signaling. IRS-1 gene has not only been shown to be associated with T2DM, but also has indicated that it may significantly correlate with diabetic complications, such as coronary heart disease and obesity. The aim of this study was to evaluate changes of the lipid panel data in T2DM patients with comorbid obesity and/or essential hypertension in connection with the IRS-1 (rs2943640) polymorphism. Methods. The study involved 33 T2DM patients and 10 healthy individuals. The IRS-1 (rs2943640) polymorphism was genotyped using a TaqMan real-time polymerase chain reaction method. Blood serum lipid panel data were determined with commercially available kits using a Cobas 6000 analyzer. Results. Analysis of the serum lipid panel data depending on the presence of the C/A alleles of IRS-1 (rs2943640) polymorphism in T2DM patients, regardless of the presence/absence of comorbidities, showed significantly lower level of high-density lipoprotein cholesterol (HDL-C) and significantly higher level of non-HDL-C in the carriers of C allele vs. carriers of A allele. In T2DM patients with comorbid obesity and essential hypertension, proatherogenic lipid changes were found in both C and A alleles carriers. Analysis of the effect of IRS-1 (rs2943640) genotypes on serum lipid panel data in T2DM patients, regardless of the presence/absence of comorbidities, showed that the CC genotype carriers had more pronounced pro-atherogenic changes vs. carriers of СА and АА genotypes. In the comorbid course of T2DM (both in combination with obesity and obesity and essential hypertension), pro-atherogenic changes were found in the carriers of the CA genotype of IRS-1 (rs2943640) polymorphism. Conclusions. The presence of the C allele of IRS-1 (rs2943640) polymorphism in both homo-zygous and heterozygous states indicates increased risk of pro-atherogenic changes in T2DM patients with comorbid obesity and/or essential hypertension.

Potential Protective Role of Galectin-3 in Patients with Gonarthrosis and Diabetes Mellitus: A Cross-Sectional Study

BACKGROUND

Gonarthrosis and diabetes mellitus are two diseases that are increasingly being linked. The aim of this study was to quantify serum levels of Gal-3, pro- and anti-inflammatory cytokines (including their ratios and correlations), and participant's condition (pain, stiffness, functional limitations) in gonarthrosis patients with and without diabetes mellitus.

METHODS

A between-subject, cross-sectional experimental design was adopted. Serum levels of TNF-α, IL-6, IL-12, IL-23, IFN-γ, IL-17, IL-10, Gal-3, and WOMAC score were measured.

RESULTS

Gonarthrosis patients with diabetes mellitus had significantly (p < 0.05) lower levels of TNF-α, IL-6, IL-12, IL-17, IFN-γ, and Gal-3 compared to gonarthrosis patients without diabetes mellitus. On the other hand, IL-10/TNF-α, IL-10/IL-6, IL-10/IL-12, Gal-3/TNF-α, Gal-3/IL-6, and Gal-3/IL-12 (p = 0.001) were significantly higher (p < 0.05) in gonarthrosis with diabetes mellitus. Moderate-large correlation (p < 0.05) was detected between the serum values of Gal-3 and pro- and anti-inflammatory cytokines, including IL-12 (r = 0.575), IL-10 (r = 0.535), TNF-α (r = 0.306), and IL-23 (r = 0.323). WOMAC index was significantly lower (p < 0.05) in gonarthrosis patients without diabetes mellitus compared to gonarthrosis patients with diabetes mellitus.

CONCLUSIONS

Correlation between Gal-3 and proinflammatory cytokines and its dominance over proinflammatory cytokines implicate the potential role of Gal-3 in preventing cartilage destruction.

Association of rs9939609-FTO with metabolic syndrome components among women from Mayan communities of Chiapas, Mexico

Background

Metabolic syndrome (MetS) is a complex cluster of risk factors, considered as a polygenic and multifactorial entity. The objective of this study was to determine the association of rs9939609-FTO polymorphism and MetS components in adult women of Mayan communities of Chiapas.

Methods

In a cross-sectional study, sociodemographic, anthropometric, clinical, and biochemical data were obtained from 291 adult women from three regions of Chiapas, Mexico. The prevalence of MetS and the allele and genotype frequencies of the rs9939609-FTO were estimated. Multivariate logistic regression models were used to assess the association of the single nucleotide polymorphism (SNP) with each of the MetS components.

Results

The MetS prevalence was 60%. We found a statistically significant association between rs9939609-FTO and hyperglycemia in the dominant model (OR 2.6; 95% CI 1.3–5.3; p = 0.007).

Conclusions

Women from Mayan communities of Chiapas presented a high prevalence of MetS and a relevant association of the FTO variant with hyperglycemia. This is the first study carried out in these Mayan indigenous communities from Chiapas.

Molecular prospect of type-2 diabetes: Nanotechnology based diagnostics and therapeutic intervention

About ninety percent of all diabetic conditions account for T2D caused due to abnormal insulin secretion/ action or increased hepatic glucose production. Factors that contribute towards the aetiology of T2D could be well explained through biochemical, molecular, and cellular aspects. In this review, we attempt to explain the recent evolving molecular and cellular advancement associated with T2D pathophysiology. Current progress fabricated in T2D research concerning intracellular signaling cascade, inflammasome, autophagy, genetic and epigenetics changes is discretely explained in simple terms. Present available anti-diabetic therapeutic strategies commercialized and their limitations which are needed to be acknowledged are addressed in the current review. In particular, the pre-eminence of nanotechnology-based approaches to nullify the inadequacy of conventional anti-diabetic therapeutics and heterogeneous nanoparticulated systems exploited in diabetic researches are also discretely mentioned and are also listed in a tabular format in the review. Additionally, as a future prospect of nanotechnology, the review presents several strategic hypotheses to ameliorate the austerity of T2D by an engineered smart targeted nano-delivery system. In detail, an effort has been made to hypothesize novel nanotechnological based therapeutic strategies, which exploits previously described inflammasome, autophagic target points. Utilizing graphical description it is explained how a smart targeted nano-delivery system could promote β-cell growth and development by inducing the Wnt signaling pathway (inhibiting Gsk3β), inhibiting inflammasome (inhibiting NLRP3), and activating autophagic target points (protecting Atg3/Atg7 complex from oxidative stress) thereby might ameliorate the severity of T2D. Additionally, several targeting molecules associated with autophagic and epigenetic factors are also highlighted, which can be exploited in future diabetic research.

[Association of polymorphisms of genes TCF7L2, FABP2, KCNQ1, ADIPOQ with the prognosis of the development of type 2 diabetes mellitus]

AIM

To study the possibility of using polymorphisms of genesTCF7L2,FABP2,KCNQ1,ADIPOQas markers for predicting the development of type 2 diabetes mellitus (T2D) in the population of Novosibirsk.

MATERIALS AND METHODS

On the basis of prospective observation of a representative population sample of residents of Novosibirsk (HAPIEE), 2 groups were formed according to the case-control principle (case people who had diabetes mellitus 2 over 10 years of observation, and control people who did not developed disorders of carbohydrate metabolism). T2D group (n=443, mean age 56.26.7 years, men 29.6%, women 70.4%), control group (n=532, mean age 56.17.1 years, men 32.7%, women 67.3%). DNA was isolated by phenol-chloroform extraction. Genotyping was performed by the method of polymerase chain reaction with subsequent analysis of restriction fragment length polymorphism, polymerase chain reaction in real time. Statistical processing was carried out using the SPSS 16.0 software package.

RESULTS AND DISCUSSION

No significant effect of rs1799883 of theFABP2gene, rs2237892 of theKCNQ1gene, and rs6773957 of theADIPOQgene on the risk of developing T2D was found. Genotypes TT and TC rs7903146 of theTCF7L2gene are genotypes for the risk of developing T2D (relative risk RR 3.90, 95% confidence interval CI 2.316.61,p0.001; RR 1.86, 95% CI 1.422.43,p0.001, respectively). The CC genotype rs7903146 of theTCF7L2gene is associated with a protective effect against T2D (RR 0.37, 95% CI 0.290.49,p0.001). When theTCF7L2gene is included in the model for assessing the risk of developing T2D rs7903146, it retains its significance in both men and women.

CONCLUSION

The rs7903146 polymorphism of theTCF7L2gene confirmed its association with the prognosis of the development of T2D, which indicates the possibility of considering it as a candidate for inclusion in a diabetes risk meter. Variants of risk meters have been developed to assess the prognosis of the development of diabetes mellitus 2 in men and women aged 4569 years during 10 years of follow-up. The association with the prognosis of the development of T2D polymorphisms rs1799883 of theFABP2gene, rs2237892 of theKCNQ1gene and rs6773957 of theADIPOQgene was not found.

Common genetic variation in obesity, lipid transfer genes and risk of Metabolic Syndrome: Results from IDEFICS/I.Family study and meta-analysis

As the prevalence of metabolic syndrome (MetS) in children and young adults is increasing, a better understanding of genetics that underlie MetS will provide critical insights into the origin of the disease. We examined associations of common genetic variants and repeated MetS score from early childhood to adolescence in a pan-European, prospective IDEFICS/I.Family cohort study with baseline survey and follow-up examinations after two and six years. We tested associations in 3067 children using a linear mixed model and confirmed the results with meta-analysis of identified SNPs. With a stringent Bonferroni adjustment for multiple comparisons we obtained significant associations(p < 1.4 × 10⁻⁴) for 5 SNPs, which were in high LD (r² > 0.85) in the 16q12.2 non-coding intronic chromosomal region of FTO gene with strongest association observed for rs8050136 (effect size(β) = 0.31, p_Wald = 1.52 × 10⁻⁵). We also observed a strong association of rs708272 in CETP with increased HDL (p = 5.63 × 10⁻⁴⁰) and decreased TRG (p = 9.60 × 10⁻⁵) levels. These findings along with meta-analysis advance etiologic understanding of childhood MetS, highlighting that genetic predisposition to MetS is largely driven by genes of obesity and lipid metabolism. Inclusion of the associated genetic variants in polygenic scores for MetS may prove to be fundamental for identifying children and subsequently adults of the high-risk group to allow earlier targeted interventions.

Determination of individual type 2 diabetes risk profile in the North East Indian population & its association with anthropometric parameters

Background & objectives:

Diabetes genomics research has illuminated single nucleotide polymorphism (SNP) in several genes including, fat mass and obesity associated (FTO) (rs9939609 and rs9926289), potassium voltage-gated channel subfamily J member 11 (rs5219), SLC30A8 (rs13266634) and peroxisome proliferator-activated receptor gamma 2 (rs1805192). The present study was conducted to investigate the involvement of these polymorphisms in conferring susceptibility to type 2 diabetes (T2D) in the North East Indian population, and also to establish their association with anthropometric parameters.

Methods:

DNA was extracted from blood samples of 155 patients with T2D and 100 controls. Genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism and DNA sequencing. To confirm the association between the inheritance of SNP and T2D development, logistic regression analysis was performed.

Results:

For the rs9939609 variant (FTO), the dominant model AA/(AT+TT) revealed significant association with T2D [odds ratio (OR)=2.03, P=0.021], but was non-significant post correction for multiple testing (P=0.002). For the rs13266634 variant (SLC30A8), there was considerable but non-significant difference in the distribution pattern of genotypic polymorphisms between the patients and the controls (P=0.004). Significant association was observed in case of the recessive model (CC+CT)/TT (OR=4.56 P=0.001), after adjusting for age, gender and body mass index. In addition, a significant association (P=0.001) of low-density lipoprotein (mg/dl) could be established with the FTO (rs9926289) polymorphism assuming dominant model.

Interpretation & conclusions:

The current study demonstrated a modest but significant effect of SLC30A8 (rs13266634) polymorphisms on T2D predisposition. Considering the burgeoning prevalence of T2D in the Indian population, the contribution of these genetic variants studied, to the ever-increasing number of T2D cases, appears to be relatively low. This study may serve as a foundation for performing future genome-wide association studies (GWAS) involving larger populations.

Assessment of FTO Gene Polymorphism and its Association with Type 2 Diabetes Mellitus in North Indian Populations

FTO gene polymorphism related to type 2 diabetes and obesity was studied in this north Indian population. This study was done, due to a continuous increase in the risk of obesity and type 2 diabetes in north Indian population, because of lifestyle and genetic variations. Clinically diagnosed subjects of type 2 diabetes mellitus (as per ADA criteria) were taken as cases and age and sex matched subjects without any associated illness were taken as controls. Obesity was estimated by calculating waist circumference and BMI in the study cases and controls. For genetic variation, DNA was isolated with Quaigen kit method and isolated DNA was amplified with PCR. Amplified DNA was resolved in 1% agarose gel electrophoresis. The Hardy-Weinberg equilibrium, OR, CI and P value were calculated using standard protocols. FTO gene polymorphism (SNP 9940128) was found to be significantly correlated with type 2 diabetes mellitus and obesity. The AG genotype frequency was observed to be higher (13.09%) with (P < 0.0001) in the cases as compared to controls. Logistic regression analysis was conducted for AG and GG genotypes with respect to AA. In this novel study genetic co-relation was observed between FTO gene polymorphisms and type 2 diabetes and obesity in the north Indian population.

Associations between the components of metabolic syndrome and the polymorphisms in the peroxisome proliferator-activated receptor gamma (PPAR-γ), the fat mass and obesity-associated (FTO), and the melanocortin-4 receptor (MC4R) genes

INTRODUCTION

Metabolic syndrome (MetS) is regarded as a set of abnormalities, increasing the risk of serious functioning disorders. It can develop as a result of genetic predisposition.

AIM

The aim of this study was to establish associations between MetS-related abnormalities and the PPAR-γ rs1801282, FTO rs9939609, and MC4R rs17782313 polymorphisms.

MATERIAL AND METHODS

The study involved 425 women aged 45-60 years. The participants were surveyed and subjected to anthropometric, biochemical and genetic analysis.

RESULTS

In the recessive inheritance model for the FTO polymorphism, a statistically significant relationship was demonstrated between the A/A genotype and glycemia. The results obtained in the codominant and overdominant models for the PPAR-y polymorphism showed a tendency to statistical significance (the C/G genotype inclined to hypertriglyceridemia), and were statistically significant in the codominant, dominant, and recessive models (the C/C genotype predisposed to increased blood pressure).

CONCLUSIONS

1. MetS-related abnormalities can be genetically determined, however only some of these relationships can be demonstrated due to the categorical division of symptoms according to the IDF criteria from 2009. 2. The A/A genotype of the FTO rs9939609 polymorphism increases the risk of hyperglycemia, and the C/C genotype of the PPAR-γ rs1801282 variant entails elevated blood pressure in 45-60-year-old women.

Genetic, Functional, and Immunological Study of ZnT8 in Diabetes

Zinc level in the body is finely regulated to maintain cellular function. Dysregulation of zinc metabolism may induce a variety of diseases, e.g., diabetes. Zinc participates in insulin synthesis, storage, and secretion by functioning as a "cellular second messenger" in the insulin signaling pathway and glucose homeostasis. The highest zinc concentration is in the pancreas islets. Zinc accumulation in cell granules is manipulated by ZnT8, a zinc transporter expressed predominately in pancreatic α and β cells. A common ZnT8 gene (SLC30A8) polymorphism increases the risk of type 2 diabetes mellitus (T2DM), and rare mutations may present protective effects. In type 1 diabetes mellitus (T1DM), autoantibodies show specificity for binding two variants of ZnT8 (R or W at amino acid 325) dictated by a polymorphism in SLC30A8. In this review, we summarize the structure, feature, functions, and polymorphisms of ZnT8 along with its association with diabetes and explore future study directions.