Obesity-related Single Nucleotide Polymorphisms Research Articles

Survey on Interaction Between Nutrient Status and Selected Polymorphisms in Association with Weight Loss of Patients with Severe Obesity Underwent Bariatric Surgery.

There is little information about the effect of single nucleotide polymorphisms (SNP) and nutritional status and weight loss after bariatric surgery. This study investigated the interactive effect of eight obesity-related SNPs and nutritional status on weight loss after Roux-en-Y gastric bypass (RYGB). This is a case-control study. After 1-year follow-up, the patients who underwent RYGB were dividing into two groups. The case group consisted of patients who lost more than 50% of their excess body weight (EBW%) 1year after the surgery. The control group included patients who lost < 50% of EBW at same time frame. Then, the relationship between eight SNPs related to UCP2, FTO, LEPR, GHRL, and NPY genes with weight loss were checked. In this study, 160 patients were recruited. The median of age for case and control group were 43 and 42 respectively. The presence of mutant variant NPYrs16147 had a significant relationship in terms of weight loss between the two groups (P > 0.05). In dominant model, two SNPs, UCP2 rs659366 and UCP2 rs660339, showed protective effect of the vitamin D deficiency. In conclusion, the presence mutant variant of NPYrs16147 is directly related to the incidence of weight loss greater than 50% of EBW. However, it is apparent individual behavioral, dietary, and other factors may have more influence on weight loss among patients underwent RYGB.

Deciphering the Interplay between Genetic Risk Scores and Lifestyle Factors on Individual Obesity Predisposition.

Obesity's variability is significantly influenced by the interplay between genetic and environmental factors. We aimed to integrate the combined impact of genetic risk score (GRSBMI) with physical activity (PA), sugar-sweetened beverages (SSB), wine intake, and eating habits score (EHS) on obesity predisposition risk. Adults' (n = 5824) data were analyzed for common obesity-related single nucleotide polymorphisms and lifestyle habits. The weighted GRSBMI was constructed and categorized into quartiles (Qs), and the adjusted multivariate logistic regression models examined the association of GRSBMI with obesity (BMI ≥ 30) and lifestyle factors. GRSBMI was significantly associated with obesity risk. Each GRSBMI unit was associated with an increase of 3.06 BMI units (p ≤ 0.0001). PA markedly reduced obesity risk across GRSBMI Qs. Inactive participants' (≥90 min/week) mean BMI was higher in GRSBMI Q3-Q4 compared to Q1 (p = 0.003 and p < 0.001, respectively). Scoring EHS ≥ median, SSBs (≥1 cup/day), and non-wine drinking were associated with higher BMI within all GRSBMI Qs compared to EHS < median, non-SSBs, and non-wine drinkers. Mean BMI was higher in GRSBMI Q4 compared to other quartiles (p < 0.0001) in non-wine drinkers and compared to Q1 for SSB's consumers (p = 0.07). A higher GRSBMI augmented the impact of lifestyle factors on obesity. The interplay between GRSBMI and modifiable lifestyle factors provides a tailored personalized prevention and treatment for obesity management.

A shared genetic contribution to osteoarthritis and COVID-19 outcomes: a large-scale genome-wide cross-trait analysis.

Patients with osteoarthritis (OA) are exposed to an increased risk of adverse outcomes of COVID-19, and they tend to experience disruption in access to healthcare services and exercise facilities. However, a deep understanding of this comorbidity phenomenon and the underlying genetic architecture of the two diseases is still unclear. In this study, we aimed to untangle the relationship between OA and COVID-19 outcomes by conducting a large-scale genome-wide cross-trait analysis. Genetic correlation and causal relationships between OA and COVID-19 outcomes (critical COVID-19, COVID-19 hospitalization, and COVID-19 infection) were estimated by linkage disequilibrium score regression and Mendelian Randomization approaches. We further applied Multi-Trait Analysis of GWAS and colocalization analysis to identify putative functional genes associated with both OA and COVID-19 outcomes. Significant positive genetic correlations between OA susceptibility and both critical COVID-19 (rg=0.266, P=0.0097) and COVID-19 hospitalization (rg=0.361, P=0.0006) were detected. However, there was no evidence to support causal genetic relationships between OA and critical COVID-19 (OR=1.17[1.00-1.36], P=0.049) or OA and COVID-19 hospitalization OR=1.08[0.97-1.20], P=0.143). These results were robustly consistent after the removal of obesity-related single nucleotide polymorphisms (SNPs). Moreover, we identified a strong association signal located near the FYCO1 gene (lead SNPs: rs71325101 for critical COVID-19, Pmeta=1.02×10-34; rs13079478 for COVID-19 hospitalization, Pmeta=1.09×10-25). Our findings further confirmed the comorbidity of OA and COVID-19 severity, but indicate a non-causal impact of OA on COVID-19 outcomes. The study offers an instructive perspective that OA patients did not generate negative COVID-19 outcomes during the pandemic in a causal way. Further clinical guidance can be formulated to enhance the quality of self-management in vulnerable OA patients.

Obesity-Related Single-Nucleotide Polymorphisms and Weight Gain Following First-Line Antiretroviral Therapy.

We studied the association of obesity-related single-nucleotide polymorphisms (OR-SNPs) with weight gain after antiretroviral therapy (ART) in people with human immunodeficiency virus (HIV; PWH). Participants were ART-naive PWH from the Spanish HIV Research Cohort who started ART from 2014 onward and had blood/DNA deposited in the cohort Biobank. The primary outcome was change in weight at 96 weeks after starting ART. We genotyped 14 OR-SNPs from a meta-analysis of genome-wide association studies of body mass index (BMI) loci. Changes over time in weight and BMI were studied using adjusted linear mixed models. A total of 1021 PWH were included. The mean weight gain over 96 weeks was 2.90 (95% confidence interval, 2.54-3.26) kg. Factors associated with higher weight gain were female sex, birth in sub-Saharan Africa, prior AIDS, CD4+ <200 cells/µL, HIV-RNA >100 000 copies/mL, negative hepatitis C virus serology, and use of tenofovir alafenamide. A significant association was found between ZC3H4 rs3810291 GG genotype and BCDIN3D/FAIM2 rs7138803 GG genotype polymorphisms and weight and BMI increase. The estimated adjusted mean (standard error [SE]) of weight gain was 4.26 (0.56) kg in ZC3H4 rs3810291 GG carriers and 2.66 (0.19) kg in AA/AG carriers (P = .007). Likewise the estimated weight gain at 96 weeks was 3.35 (0.29) kg in BCDIN3D/FAIM2 rs7138803 GG carriers and 2.51 (0.24) kg in AG/AA carriers (P = .020). Genetic factors may play a role in weight gain after ART initiation. Further work is needed to replicate our findings and understand how the identified SNPs lead to higher weight gain in this context.

Combination of Single-Nucleotide Polymorphisms and Preoperative Body Mass Index to Predict Weight Loss After Laproscopic Sleeve Gastrectomy in Chinese Patients with Body Mass Index ≥ 32.5kg/m2.

Single-nucleotide polymorphisms (SNPs) associated with obesity predict laparoscopic Roux-en-Y gastric bypass (LRYGB) and biliopancreatic diversion with duodenal switch (BPD/DS) for weight loss with good efficiency. However, prediction of weight loss after laparoscopic sleeve gastrectomy using SNPs has not been well investigated. To predict weight loss after laparoscopic sleeve gastrectomy using obesity-related SNPs and clinical variants in Chinese patients with body mass index (BMI) ≥ 32.5kg/m2. We detected 29 SNPs. Binary logistic regression was used to screen SNPs and clinical variables with predictive value. Receiver operating characteristic (ROC) curves were plotted for clinical variables, SNPs, and their combination, and areas under the ROC curve (AUC) were compared. Internal and external validation tests were performed. rs12535708, rs651821, and rs5082 were constructed as the genetic risk score (GRS). Preoperative BMI was constructed as the clinical risk score (CRS). Preoperative BMI and SNPs were constructed as the cumulative genetic risk score (CGRS). ROC curves of GRS, CRS, and CGRS showed that the optimal cutoffs were 0.831 (AUC = 0.840; sensitivity, 92.96%; specificity, 64.29%), 43.46kg/m2 (AUC = 0.830; sensitivity, 76.06%; specificity, 85.71%), and 0.921 (AUC = 0.931; sensitivity, 77.46%; specificity, 92.86%), respectively. The AUC of CGRS was significantly greater than that of CRS (P < 0.05) and greater than GRS without statistical significance. In Chinese patients with BMI ≥ 32.5kg/m2, GRS and CRS could predict weight loss success. However, CGRS was superior to GRS or CRS alone.

Changes in Novel Anthropometric Indices of Abdominal Obesity during Weight Loss with Selected Obesity-Associated Single-Nucleotide Polymorphisms: A Small One-Year Pilot Study.

Whether BMI and the competing waist circumference (WC)-based anthropometric indices are associated with obesity-related single-nucleotide polymorphisms (SNPs) is as yet unknown. The current study aimed to evaluate the anthropometric indices (fat mass index, body shape index, visceral adiposity index, relative fat mass, body roundness index, and conicity index) during a weight loss intervention in 36 obese individuals. Blood biochemical parameters (total cholesterol, low-density lipoprotein, high-density lipoprotein, and triglycerides) and three SNPs (FTO rs9939609, TFAP2B rs987237, and PLIN1 rs894160) were assessed in 22 women and 14 men (35.58 ± 9.85 years, BMI 35.04 ± 3.80 kg/m2) who completed a 12-month balanced energy-restricted diet weight loss program. Body composition was assessed via bioelectrical impedance (SECA mBCA515). At the end of the weight loss intervention, all anthropometric indices were significantly reduced (p < 0.05). For the SNP FTO rs9939609, the higher risk allele (A) was characteristic of 88.9% of the study group, in which 10 participants (27.8%) were homozygous. We found a similar distribution of alleles in TFAP2B and PLIN1. Heterozygous genotypes in FTO rs9939609 and TFAP2B rs987237 were predisposed to significant reductions in WC-based novel anthropometric indices during weight loss. The influence of PLIN1 rs894160 polymorphisms on the changes in the analyzed indices during weight loss has not been documented in the present study.

Epigenomic and Transcriptomic Prioritization of Candidate Obesity-Risk Regulatory GWAS SNPs.

Concern about rising rates of obesity has prompted searches for obesity-related single nucleotide polymorphisms (SNPs) in genome-wide association studies (GWAS). Identifying plausible regulatory SNPs is very difficult partially because of linkage disequilibrium. We used an unusual epigenomic and transcriptomic analysis of obesity GWAS-derived SNPs in adipose versus heterologous tissues. From 50 GWAS and 121,064 expanded SNPs, we prioritized 47 potential causal regulatory SNPs (Tier-1 SNPs) for 14 gene loci. A detailed examination of seven loci revealed that four (CABLES1, PC, PEMT, and FAM13A) had Tier-1 SNPs positioned so that they could regulate use of alternative transcription start sites, resulting in different polypeptides being generated or different amounts of an intronic microRNA gene being expressed. HOXA11 and long noncoding RNA gene RP11-392O17.1 had Tier-1 SNPs in their 3′ or promoter region, respectively, and strong preferences for expression in subcutaneous versus visceral adipose tissue. ZBED3-AS1 had two intragenic Tier-1 SNPs, each of which could contribute to mediating obesity risk through modulating long-distance chromatin interactions. Our approach not only revealed especially credible novel regulatory SNPs, but also helped evaluate previously highlighted obesity GWAS SNPs that were candidates for transcription regulation.

Genetic predisposition to obesity and inflammation in a tri-racial/ethnic breast cancer population

Aim: Multiple genes and genetic variants may contribute to racial/ethnic disparities in obesity-associated breast cancer diagnosis and prognosis. Therefore, we evaluate whether racial/ethnic differences in polygenic risk score (PRS) contribute to obesity and inflammatory biomarker in breast cancer patients. Methods: In a tri-racial/ethnic population of 403 breast cancer patients, 21% African American (AA), 65% Hispanic White (HW), and 14% non-Hispanic White (NHW), we evaluated racial/ethnic differences in obesity PRS, the association between PRS and an inflammatory biomarker C-reactive protein (CRP), and its implication in bariatric surgery eligibility. The obesity PRS was constructed via a weighted risk allele model using 35 obesity-related single nucleotide polymorphisms (SNPs). SAS version 9.3 for Windows (SAS Institute, Cary, NC, USA) was used to perform the logistic regression analysis. Results: About 74% of our study population were overweight or obese. The mean ± SD of obesity PRS was 45.03 ± 10.66 for obese patients and 39.36 ± 8.81 for non-obese patients (P &lt; 0.0001). AA patients had a significantly higher obesity PRS than HW and NHW (P &lt; 0.0001). The obesity PRS significantly correlated with body mass index and CRP levels (P &lt; 0.0001) and was associated with bariatric surgery eligibility (OR = 4.32, 95%CI: 1.89-9.87). Conclusion: In summary, multiple obesity-associated SNPs contribute to racial/ethnic disparities in obesity of breast cancer patients; the obesity PRS has application in identifying breast cancer patients with higher genetic risk for obesity who may benefit from more aggressive weight management, such as bariatric surgery to improve breast cancer clinical outcomes.

Obesity-related genetic polymorphisms are associated with the risk of early puberty in Han Chinese girls.

To explore the association between obesity and precocious puberty from the perspective of genetic polymorphism. Two hundred and ninety-eight pairs of girls in early puberty and age-matched controls (±3 months) were recruited. The genotypes of four obesity-related single-nucleotide polymorphism (SNP) loci (rs10968576, rs12935153, rs4674340 and rs7635103) were determined and the effect of variation on early puberty in Chinese Han girls was evaluated. The unstimulated luteinizing hormone (LH), follicle-stimulating hormone and estradiol levels were also measured to determine the relationship with SNP polymorphisms. The effect allele A of rs12935153 was associated with early puberty (odds ratio [OR] = 1.256, 95% confidence interval [CI]: 1.010-1.585), but the significance disappeared after multiple comparisons. After adjusting for body mass index, rs12935153 variation increased the risk of early puberty in additive (OR = 1.589, 95% CI: 1.222-2.066), dominant (OR = 1.788, 95% CI: 1.210-2.642) and recessive (OR = 1.915, 95% CI: 1.207-3.038) models of inheritance. Individuals harbouring AA genotype in rs12935153 had a risk of higher LH levels than that of wild type (OR = 1.668, 95% CI: 1.093-2.546). The association between obesity and precocity can be explained from a genetic perspective. Our study suggests that variations in rs12935153 increase the risk of early puberty in Chinese girls. Further studies are needed to verify our findings.

Associations between KCNQ1 and ITIH4 gene polymorphisms and infant weight gain in early life.

An earlier meta-analysis of genome-wide association studies in Asian populations detected five novel body mass index-associated single-nucleotide polymorphisms (SNPs), including potassium voltage-gated channel subfamily Q member 1 (KCNQ1) (rs2237892), ALDH2/MYL2 (rs671, rs12229654), ITIH4 (rs2535633), and NT5C2 (rs11191580). Whether these SNPs take effect in early life, for example, affect infant rapid weight gain (RWG), is unclear. We obtained genomic DNA from 460 term infants with normal birth weight. RWG was defined as the change of weight-for-age standardized Z-score, calculated according to the Children Growth Standard released by the World Health Organization, from birth to 3 months of age >0.67. Using genetic models, associations between the candidate SNPs and infant RWG were examined, along with the interaction between the SNPs and the potential risk factors. RWG was presented in 225 of 460 infants. SNP rs2535633 and rs2237892 were associated with the risk of RWG. Both additive and multiplicative interaction effects were found between infant delivery mode and rs2237892. The negative association between the rs2237892 T allele and infant RWG was only observed in vaginally delivered infants. Obesity-related loci rs2535633 and rs2237892 are associated with infant RWG in the first 3 months of infancy. The relationship between rs2237892 and infant RGW might be moderated by cesarean delivery. Genetic predisposition is an essential aspect to understand infant weight gain. Obesity-related SNPs, rs2535633 and rs2237892, are associated with RWG in very early years of life. The negative association between rs2237892 T allele and RWG is only observed in infants delivered vaginally instead of cesarean section.

Sex-Specific Associations between Gut Prevotellaceae and Host Genetics on Adiposity.

The gut microbiome has been recognized as a tool for understanding adiposity accumulation and for providing personalized nutrition advice for the management of obesity and accompanying metabolic complications. The genetic background is also involved in human energy homeostasis. In order to increase the value of nutrigenetic dietary advice, the interplay between genetics and microbiota must be investigated. The purpose of the present study was to evaluate interactive associations between gut microbiota composition and 95 obesity-related single nucleotide polymorphisms (SNPs) searched in the literature. Oral mucosa and fecal samples from 360 normal weight, overweight and obese subjects were collected. Next generation genotyping of these 95 SNPs and fecal 16S rRNA sequencing were performed. A genetic risk score (GRS) was constructed with 10 SNPs statistically or marginally associated with body mass index (BMI). Several microbiome statistical analyses at family taxonomic level were applied (LEfSe, Canonical Correspondence Analysis, MetagenomeSeq and Random Forest), and Prevotellaceae family was found in all of them as one of the most important bacterial families associated with BMI and GRS. Thus, in this family it was further analyzed the interactive association between BMI and GRS with linear regression models. Interestingly, women with higher abundance of Prevotellaceae and higher GRS were more obese, compared to women with higher GRS and lower abundance of Prevotellaceae. These findings suggest relevant interrelationships between Prevotellaceae and the genetic background that may determine interindividual BMI differences in women, which opens the way to new precision nutrition-based treatments for obesity.

Applicability of Obesity-Related SNPs and their Effect Size Measures Defined on Populations with European Ancestry for Genetic Risk Estimation among Roma.

Investigations on the impact of genetic factors on the development of obesity have been limited regarding the Roma population—the largest and most vulnerable ethnic minority in Europe of Asian origin. Genetic variants identified from genetic association studies are primarily from European populations. With that in mind, we investigated the applicability of data on selected obesity-related single nucleotide polymorphisms (SNPs), obtained from the Hungarian general (HG) population of European origin, on the Hungarian Roma (HR) population. Twenty preselected SNPs in susceptible alleles, known to be significantly associated with obesity-related phenotypes, were used to estimate the effect of these SNPs on body mass index (BMI) and waist circumference (WC) in HG (N = 1783) and HR (N = 1225) populations. Single SNP associations were tested using linear and logistic regression models, adjusted for known covariates. Out of 20 SNPs, four located in FTO (rs1121980, rs1558902, rs9939609, and rs9941349) showed strong association with BMI and WC as continuous variables in both samples. Computations based on Adult Treatment Panel III (ATPIII) and the International Diabetes Federation’s (IDF) European and Asian criteria showed rs9941349 in FTO to be associated only with WC among both populations, and two SNPs (rs2867125, rs6548238) in TMEM18 associated with WC only in HG population. A substantial difference (both in direction and effect size) was observed only in the case of rs1801282 in PPARγ on WC as a continuous outcome. Findings suggest that genetic risk scores based on counting SNPs with relatively high effect sizes, defined based on populations with European ancestry, can sufficiently allow estimation of genetic susceptibility for Roma. Further studies are needed to clarify the role of SNP(s) with protective effect(s).

Weighting approaches for a genetic risk score and an oxidative stress score for predicting the incidence of obesity.

We aimed to predict the incidence of obesity in a Korean population using a genetic risk score (GRS) constructed with obesity-related single nucleotide polymorphisms (SNPs) along with an oxidative stress score (OSS). A total of 9460 Korean subjects and 356 974 SNPs were included. The GRS was constructed using three significant obesity-related SNP loci, and the OSS was calculated with three reliable oxidative stress biomarkers. The GRS showed a more significant association with increased obesity (OR = 2.879) than did individual SNPs after adjusting for age and sex. Three oxidative stress biomarkers, including malondialdehyde, oxidized low-density lipoprotein, and 8-epi-prostaglandin F2α , showed significantly high levels in the obese group. The OSS, which was the sum of each oxidative stress biomarker score, showed a markedly high association with the incidence of obesity, with an OR of 3.213. Based on the results of the regression tests and a receiver-operating characteristic (ROC) curve analysis, we found that HOMA-IR, high-sensitivity C-reactive protein (hs-CRP), the GRS, and the OSS were the most relevant factors for the increased risk of obesity and were significantly associated with the incidence of obesity. The area under the ROC curve was improved when the GRS was added to the model (from 74.2% to 75.1%). We first identified that subjects with an obesity GRS and a high OSS might have a higher risk of obesity. Our findings and weighting approaches were effective in predicting the incidence of obesity; furthermore, the GRS is a relevant factor that significantly predicts the risk of obesity.

GNPDA2 Gene Affects Adipogenesis and Alters the Transcriptome Profile of Human Adipose-Derived Mesenchymal Stem Cells.

Background Genome-wide association studies have found an obesity-related single-nucleotide polymorphism rs10938397 near the glucosamine-6-phosphate deaminase 2 gene (GNPDA2) encoding, an enzyme that catalyzes the deamination of the glucosamine-6-phosphate involved in the hexosamine signaling pathway, but the molecular mechanisms underlying the missing link between GNPDA2 and obesity remain elusive. Methods As obesity is accompanied by an increase in the size and the number of adipocytes, the present study investigates the possible mechanism of the GNPDA2 in adipogenesis using GeneChip® Human Transcriptome Array 2.0 in human adipose-derived mesenchymal stem cells. Results We found that overexpression of GNPDA2 enhanced accumulation of lipid droplets, and knocking down the gene decreased accumulation of lipid droplets. GO term enrichment analysis indicated that most differentially expressed genes (DEGs) affected by deficiency of GNPDA2 have functions to lipid and glucose metabolism. Further KEGG enrichment analysis showed that the greatest proportion of DEGs are involved in thermogenesis, peroxisome proliferator-activated receptor (PPAR) signaling pathway, carbon metabolism, and fatty acid metabolism including fatty acid degradation, elongation, and biosynthesis. Conclusion These findings suggest that GNPDA2 may be a critical gene for lipid and glucose metabolism, and the expression level of GNPDA2 alters the transcriptome profile of human adipose-derived mesenchymal stem cells.

313-LB: Weighting Approaches for a Genetic Risk Score and an Oxidative Stress Score for Predicting the Incidence of Obesity in a Korean Population

Background/Objectives: We aimed to predict the incidence of obesity in a Korean population using a genetic risk score (GRS) constructed with obesity-related single nucleotide polymorphisms (SNPs) along with an oxidative stress score (OSS). Subjects/Methods: A total of 9,460 Korean subjects and 356,974 SNPs were included. The GRS was constructed using three significant obesity-related SNP loci, and the OSS was calculated with three reliable oxidative stress biomarkers. Results: In an association study, the top three SNPs, rs2846412, rs58424360, and rs591120, showed profound associations with obesity in a Korean population (all FDR &amp;lt; 0.1). The GRS showed a more significant association with increased obesity (OR = 2.879, 95% CI = 2.283-3.630) than individual SNPs did after adjusting for age and sex. Three oxidative stress biomarkers, including malondialdehyde (MDA), oxidized low-density lipoprotein (ox-LDL), and 8-epi-prostaglandin F2α (8-epi-PGF2α), showed significantly high levels in the obese group. Moreover, the OSS, which was the sum of each oxidative stress biomarker score, showed a markedly high association with the incidence of obesity, with an OR of 3.213 (p = 3.57E-18). Based on the results from the regression tests and a receiver-operating characteristic (ROC) curve analysis, we found that HOMA-IR, hs-CRP, the GRS, and the OSS were the most relevant factors for the incremental risk of obesity and were significantly associated with the incidence of obesity. The area under the ROC curve (AUROC) was improved when the GRS was added to the model with the OSS and two obesity-related parameters (from 74.2% to 75.1%). Conclusions: We first identified that subjects with an obesity GRS and a high OSS may have a higher risk of obesity. Our findings and weighting approaches were effective in predicting the incidence of obesity; furthermore, the GRS is a relevant factor that significantly predicts the risk of obesity. Disclosure M. Kim: None. H. Yoo: None. Y. Han: None. J. Lee: None. Funding Korean Ministry of Health and Welfare (HI13C0715); Korean National Research Foundation (NRF-2017R1C1B2007195, NRF-2012M3A9C4048762)

Newly identified set of obesity-related genotypes and abdominal fat influence the risk of insulin resistance in a Korean population.

We aimed to identify obesity-related single-nucleotide polymorphism (SNP) loci in a Korean population and construct an obesity genetic risk score (GRS) to examine the association of the genetic predisposition to obesity with insulin resistance (IR). In total, 9675 subjects were included, and 7666 of these subjects were used for replication. A GRS was constructed using the SNP loci that overlapped in both cohort sets. The subjects showed a trend toward an increase in body mass index, waist circumference, systolic/diastolic blood pressure, homeostatic model assessment (HOMA)-IR, HOMA-B, and levels of insulin, triglyceride, and alanine aminotransferase across the tertiles of obesity GRS, while the adiponectin level showed a trend toward a decrease with increasing GRS. The associations between the obesity GRS and the measures of fasting insulin, HOMA-IR, and adiponectin were significant after adjusting for confounding factors. Moreover, a significant association between obesity GRS and HOMA-IR was observed in subjects with abdominal obesity. The present results indicate that a predisposition to obesity may affect IR in the Korean population and that abdominal fat may alter or modify the genetic effects. Furthermore, the set of obesity-related genotypes and abdominal fat may play interactive roles in determining the risk of IR.

Birthweight, time-varying adiposity growth and early menarche in girls: A Mendelian randomisation and mediation analysis

To explore the causal effect of time-varying z-BMI growth on early menarche using Mendelian randomisation (MR); to identify critical adiposity predictors of early menarche; to compare the effects of birthweight and time-varying z-BMI growth as mediators of the path from genes to early menarche using mediation analysis. We used data from the Taiwan Children Health Study with 21 obesity-related single-nucleotide polymorphisms (SNPs) to yield genetic (instrumental variable)IVs for adiposity. Children with available data on genotyping, birthweight, adiposity, and menarcheal age were included. In MR analyses, results based on the time-varying z-BMI growth show more statistical power and capture more information of adiposity growth (p=0.01) than those based on single point z-BMI (p=0.02). Among adiposity measures, critical predictors of early menarche are fat free mass (RR=1.33, 95% CI 1.07-1.65) and waist/height ratio (RR=1.27, 95% CI 1.03-1.56). Other potential predictors of early menarche are sum of skinfold (RR=1.24, 95% CI 1.03-1.48) and total body fat (RR=1.20, 95% CI 1.05-1.38). In both one-mediation and multi-mediation analyses, time-varying z-BMI growth in the prepubertal years plays a crucial mediator in the pathway from the genes to early menarche. This study discovered that greater prepubertal adiposity growth is a crucial mediator in the path from genes to early menarche. For girls with genes positively associated with obesity; and/or of lower birthweight, a strategy to prevent childhood adiposity should be implemented in order to avoid early menarche development.

Critical Enzymatic Functions of FTO in Obesity and Cancer.

Fat mass and obesity-associated protein (FTO) single-nucleotide polymorphisms (SNPs) have been linked to increased body mass and obesity in humans by genome-wide association studies (GWAS) since 2007. Although some recent studies suggest that the obesity-related SNPs in FTO influence obesity susceptibility likely through altering the expression of the adjacent genes such as IRX3 and RPGRIP1L, rather than FTO itself, a solid link between the SNP risk genotype and the increased FTO expression in both human blood cells and fibroblasts has been reported. Moreover, multiple lines of evidence have demonstrated that FTO does play a critical role in the regulation of fat mass, adipogenesis, and body weight. Epidemiology studies also showed a strong association of FTO SNPs and overweight/obesity with increased risk of various types of cancers. As the first identified messenger RNA N6-methyladenosine (m6A) demethylase, FTO has been shown recently to play m6A-dependent roles in adipogenesis and tumorigenesis (especially in the development of leukemia and glioblastoma). Given the critical roles of FTO in cancers, the development of selective and effective inhibitors targeting FTO holds potential to treat cancers. This mini review discusses the roles and underlying molecular mechanisms of FTO in both obesity and cancers, and also summarizes recent advances in the development of FTO inhibitors.

Associations of Two Obesity-Related Single-Nucleotide Polymorphisms with Adiponectin in Chinese Children.

Purpose. Genome-wide association studies have found two obesity-related single-nucleotide polymorphisms (SNPs), rs17782313 near the melanocortin-4 receptor (MC4R) gene and rs6265 near the brain-derived neurotrophic factor (BDNF) gene, but the associations of both SNPs with other obesity-related traits are not fully described, especially in children. The aim of the present study is to investigate the associations between the SNPs and adiponectin that has a regulatory role in glucose and lipid metabolism. Methods. We examined the associations of the SNPs with adiponectin in Beijing Child and Adolescent Metabolic Syndrome (BCAMS) study. A total of 3503 children participated in the study. Results. The SNP rs6265 was significantly associated with adiponectin under an additive model (P = 0.02 and 0.024, resp.) after adjustment for age, gender, and BMI or obesity statuses. The SNP rs17782313 was significantly associated with low adiponectin under a recessive model. No statistical significance was found between the two SNPs and low adiponectin after correction for multiple testing. Conclusion. We demonstrate for the first time that the SNP rs17782313 near MC4R and the SNP rs6265 near BDNF are associated with adiponectin in Chinese children. These novel findings provide important evidence that adiponectin possibly mediates MC4R and BDNF involved in obesity.

Effect of dietary energy and polymorphisms in BRAP and GHRL on obesity and metabolic traits

Obesity, a risk factor for all-cause and cardiovascular mortality, is a major health concerns among middle-aged men. The aim of this study was to investigate a possible association of dietary habits and obesity related single nucleotide polymorphisms (SNPs) with obesity and metabolic abnormalities. We conducted a retrospective cohort study using annual health examination data of 5112 male workers, obtained between 2007 and 2011. Average dietary energy was estimated using electronically collected meal purchase data from cafeteria. We examined 8 SNPs related to obesity: GHRL rs696217, PPARG rs1175544, ADIPOQ rs2241766, ADIPOQ rs1501299, PPARD rs2016520, APOA5 rs662799, BRAP rs3782886, and ITGB2 rs235326. We also examined whether SNPs that were shown to associate with obesity affect other metabolic abnormalities such as blood pressure (BP), glucose, and lipid profile. Average dietary energy significantly associated with increased abdominal circumference (AC) and body mass index (BMI). The odds ratios (ORs) of overweight and obesity also increased. The major allele of rs696217 significantly increased BMI and an increased OR with obesity, while the minor allele of rs3782886 was associated with significantly decreased AC and the decreased ORs with overweight and obesity. The minor allele of rs3782886 was also associated with significantly decreased systolic BP (SBP), triglyceride (TG), high-density lipoprotein (HDL), and fasting blood sugar (FBS), while rs696217 was not associated with other metabolic abnormalities. Average dietary energy in lunch, rs3782886, and rs696217 were associated with obesity, and rs3782886 was associated with other metabolic abnormalities.