ABSTRACT
A genome-wide association study (GWAS) is a powerful tool in investigating genetic contribution, which is a crucial factor in the development of complex multifactorial diseases, such as type 2 diabetes mellitus. Type 2 diabetes mellitus is a major healthcare burden in the Western Pacific region; however, there is limited availability of genetic-associated data for type 2 diabetes in Southeast Asia, especially among the Kinh Vietnamese population. This lack of information exacerbates global healthcare disparities. In this study, 997 Kinh Vietnamese individuals (503 with type 2 diabetes and 494 controls) were prospectively recruited and their clinical and paraclinical information was recorded. DNA samples were collected and whole genome genotyping was performed. Standard quality control and genetic imputation using the 1000 Genomes database were executed. A polygenic risk score for type 2 diabetes was generated in different models using East Asian, European, and mix ancestry GWAS summary statistics as training datasets. After quality control and genetic imputation, 107 polymorphisms reached suggestive statistical significance for GWAS (≤5 × 10-6) and rs11079784 was one of the potential markers strongly associated with type 2 diabetes in the studied population. The best polygenic risk score model predicting type 2 diabetes mellitus had AUC = 0.70 (95% confidence interval = 0.62-0.77) based on a mix of ancestral GWAS summary statistics. These data show promising results for genetic association with a polygenic risk score estimation in the Kinh Vietnamese population; the results also highlight the essential role of population diversity in a GWAS of type 2 diabetes mellitus.
Subject(s)
Diabetes Mellitus, Type 2 , Genetic Predisposition to Disease , Genome-Wide Association Study , Multifactorial Inheritance , Polymorphism, Single Nucleotide , Adult , Aged , Female , Humans , Male , Middle Aged , Case-Control Studies , Diabetes Mellitus, Type 2/genetics , Genetic Risk Score , Multifactorial Inheritance/genetics , Pilot Projects , Polymorphism, Single Nucleotide/genetics , Risk Factors , Southeast Asian People/genetics , Vietnam/epidemiologyABSTRACT
Summary: Mitochondrial diseases are a group of rare diseases presenting with heterogeneous clinical, biochemical, and genetic disorders caused by mutations in the mitochondrial or nuclear genome. Multiple organs can be affected, particularly those with high energy demand. Diabetes is a common endocrine manifestation of mitochondrial diseases. The onset of mitochondrial diabetes can be latent or acute, and the presenting phenotype can be type 1- or type 2-like. Studies show that diabetes ais associated with latent progression of cognitive decline in patients with mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome. Herein, we report a case of rapid cognitive decline after the acute onset of diabetes in a patient with MELAS syndrome. The patient was a 36-year-old woman who was hospitalized due to hyperglycemic crisis and seizures. She was diagnosed with MELAS syndrome two years previously, and had gradually progressing dementia and hearing loss. However, following the acute onset of diabetes, she developed rapid cognitive decline and loss of ability to perform daily activities. In conclusion, the acute onset of diabetes could be an associated risk factor for rapid cognitive decline in patients with MELAS syndrome. Thus, these patients as well as healthy carriers with related genetic mutations should undergo diabetes education and screening tests. Moreover, clinicians should be aware of the possibility for acute onset of hyperglycemic crisis, particularly in the presence of triggering factors. Learning points: Diabetes is a common endocrine manifestation of mitochondrial diseases, presenting with a type 1- or type 2-like phenotype depending on the level of insulinopenia. Metformin should be avoided in patients with mitochondrial diseases to prevent metformin-induced lactic acidosis. Mitochondrial diabetes can manifest before or after the onset of MELAS syndrome. In patients with MELAS syndrome, diabetes can initially manifest with a life-threatening severe hyperglycemic crisis and can cause rapid cognitive decline. Diabetes screening tests (e.g. hemoglobin A1c, oral glucose tolerance test, or random blood glucose level measurement) should be performed either systematically or in the presence of symptoms, particularly after triggering events. Genetic testing and counseling should be provided to patients and their families for the purpose of better understanding the inheritance, progression, and possible outcomes of the disease.
ABSTRACT
PURPOSE: Genetic factors play an important role in the development of type 2 diabetes mellitus (T2DM) and metabolic syndrome (MetS). However, few genetic association studies related to these disorders have been performed with Vietnamese subjects. In this study, the potential associations of ADIPOQ single nucleotide polymorphisms (SNPs) with T2DM and MetS in a Kinh Vietnamese population were investigated. PATIENTS AND METHODS: A study with 768 subjects was conducted to examine the associations of four ADIPOQ SNPs (rs266729, rs1501299, rs3774261, and rs822393) primarily with T2DM and secondarily with MetS. The TaqMan SNP genotyping assay was used to determine genotypes from subjects' DNA samples. RESULTS: After statistical adjustment for age, sex, and body mass index, the ADIPOQ SNP rs266729 was found to be associated with increased risk of T2DM under multiple inheritance models: codominant (OR = 2.30, 95% CI = 1.16-4.58), recessive (OR = 2.17, 95% CI = 1.11-4.26), and log-additive (OR = 1.32, 95% CI = 1.02-1.70). However, rs1501299, rs3774261, and rs822393 were not associated with risk for T2DM. Additionally, rs266729, rs3774261, and rs822393 were statistically associated with MetS, while rs1501299 was not. Haplotype analysis showed a strong linkage disequilibrium between the SNP pairs rs266729/rs822393 and rs1501299/rs3774261, and the haplotype rs266729(G)/rs822393(T) was not statistically associated with MetS. CONCLUSION: The results show that rs266729 is a lead candidate SNP associated with increased risk of developing T2DM and MetS in a Kinh Vietnamese population, while rs3774261 is associated with MetS only. Further functional characterization is needed to uncover the mechanism underlying the potential genotype-phenotype associations.
ABSTRACT
Type 2 diabetes mellitus (T2DM) is a genetically influenced disease, but few studies have been performed to investigate the genetic basis of T2DM in Vietnamese subjects. Thus, the potential associations of KCNJ11 and ABCC8 single nucleotide polymorphisms (SNPs) with T2DM were investigated in a Kinh Vietnamese population. A cross-sectional study consisting of 404 subjects including 202 T2DM cases and 202 non-T2DM controls was designed to examine the potential associations of 4 KCNJ11 and ABCC8 SNPs (rs5219, rs2285676, rs1799859, and rs757110) with T2DM. Genotypes were identified based on restriction fragment length polymorphism and tetra-primer amplification refractory mutation system polymerase chain reaction. After statistically adjusting for age, sex, and BMI, rs5219 was found to be associated with an increased risk of T2DM under 2 inheritance models: codominant (ORâ =â 2.15, 95% confidence intervals [CI]â =â 1.09-4.22) and recessive (ORâ =â 2.08, 95%CIâ =â 1.09-3.94). On the other hand, rs2285676, rs1799859, and rs757110 were not associated with an increased risk of T2DM. Haplotype analysis elucidated a strong linkage disequilibrium between the 3 SNPs, rs5219, rs2285676, and rs757110. The haplotype rs5219(A)/rs2285676(T)/rs757110(G) was associated with an increased risk of T2DM (ORâ =â 1.42, 95%CIâ =â 1.01-1.99). The results show that rs5219 is a lead candidate SNP associated with an increased risk of developing T2DM in the Kinh Vietnamese population. Further functional characterization is needed to uncover the mechanism underlying the potential genotype-phenotype associations.
Subject(s)
Diabetes Mellitus, Type 2 , Potassium Channels, Inwardly Rectifying , Humans , Polymorphism, Single Nucleotide , Diabetes Mellitus, Type 2/epidemiology , Diabetes Mellitus, Type 2/genetics , Genetic Predisposition to Disease , Cross-Sectional Studies , Potassium Channels, Inwardly Rectifying/genetics , Asian People/genetics , Sulfonylurea Receptors/geneticsABSTRACT
SUMMARY: Primary adrenal insufficiency is a rare disease and can masquerade as other conditions; therefore, it is sometimes incorrectly diagnosed. Herein, we reported the case of a 39-year-old Vietnamese male with primary adrenal insufficiency due to bilateral adrenal tuberculosis. The patient presented to the emergency room with acute adrenal crisis and a 3-day history of nausea, vomiting, epigastric pain, and diarrhoea with a background of 6 months of fatigue, weight loss, and anorexia. Abdominal CT revealed bilateral adrenal masses. Biochemically, unequivocal low morning plasma cortisol (<83 nmol/L) and high plasma adrenocorticotropic hormone levels were consistent with primary adrenal insufficiency. There was no evidence of malignancy or lymphoma. As the patient was from a tuberculosis-endemic area, extra-adrenal tuberculosis was excluded during the work up. A retroperitoneal laparoscopic left adrenalectomy was performed, and tuberculous adrenalitis was confirmed by the histopathological results. The patient was started on antituberculous therapy, in addition to glucocorticoid replacement. In conclusion, even without evidence of extra-adrenal tuberculosis, a diagnosis of bilateral adrenal tuberculosis is required. A histopathological examination has a significant role along with clinical judgement and hormonal workup in establishing a definitive diagnosis of adrenal tuberculosis without evidence of active extra-adrenal involvement. LEARNING POINTS: Primary adrenal insufficiency can be misdiagnosed as other mimicking diseases, such as gastrointestinal illness, leading to diagnostic pitfalls. Adrenal insufficiency can be confirmed with significantly low morning plasma cortisol levels of <83 nmol/L without a dynamic short cosyntropin stimulation test. Tuberculous adrenalitis is an uncommon treatable condition; however, it remains an important cause of primary adrenal insufficiency, especially in developing countries. In the absence of extra-adrenal involvement, adrenal biopsy plays a key role in the diagnostic process. Alternatively, adrenalectomy for histopathological purposes should be considered if CT scan-guided fine needle aspiration is infeasible in cases of small adrenal masses.
ABSTRACT
This paper proposes the design and implementation of a low-voltage and low-power body sensor node based on the IEEE 802.15.4 standard to collect electrocardiography (ECG) and photoplethysmography (PPG) signals. To achieve compact size, low supply voltage, and low power consumption, the proposed platform is integrated into a ZigBee mote, which contains a DC-DC booster, a PPG sensor interface module, and an ECG front-end circuit that has ultra-low current consumption. The input voltage of the proposed node is very low and has a wide range, from 0.65 V to 3.3 V. An RF energy harvester is also designed to charge the battery during the working mode or standby mode of the node. The power consumption of the proposed node reaches 14 mW in working mode to prolong the battery lifetime. The software is supported by the nesC language under the TinyOS environment, which enables the proposed node to be easily configured to function as an individual health monitoring node or a node in a wireless body sensor network (BSN). The proposed node is used to set up a wireless BSN that can simultaneously collect ECG and PPG signals and monitor the results on the personal computer.