Interactions with the MC4R rs17782313 variant, mental stress and energy intake and the risk of obesity in Genome Epidemiology Study

Functional Impact of the FADS1 rs174546 Single Nucleotide Polymorphism on Serum Lipid Levels: Insights from Molecular Mechanisms and Therapeutic Perspectives in Korean Population

SCOPE

Single nucleotide polymorphisms (SNP) in the fatty acid desaturase 1 (FADS1) gene is suggested as risk factor of metabolic diseases in genome-wide association studies (GWAS). This study hypothesized that FADS1_rs174546T associates with serum triglycerides (TG) in Korean Genome and Epidemiology Study (KoGES). In addition, functional study of SNP genotypes in cultured cells is performed.

METHODS AND RESULTS

FADS1_rs174546T is associated with high level of serum TG (effect size of variant: 6.48 ± 1.84 mg dL-1) in Korean individuals (normotriglyceridemia, n = 5128; hypertriglyceridemia, n = 3714). Functional study in cells with FADS1_rs174546T, shows reduced transcriptional activity, when compared with rs174546C. MiR-6728-3p, which is predicted to bind with rs174546T, decreases transcriptional activity of rs174546T but not in rs174546C, and it is reversed by miR-6728-3p inhibitor. Formononetin is selected as binding molecule to 3'-UTR of FADS1 and increases luciferase activity in both rs174546 (C/T). Moreover, formononetin compensates for the reduced luciferase activity by rs174546T and miR-6728-3p. Formononetin also increases endogenous FADS1 expression and long-chain polyunsaturated fatty acid (LC-PUFA) ratio.

CONCLUSION

FADS1_rs174546T is a crucial risk factor for hypertriglyceridemia in the Koreans potentially through the interaction with miR-6728-3p. Formononetin can be a potent dietary intervention to prevent and improve hypertriglyceridemia in both rs174546 (C/T) populations.

Interactions between Polygenetic Variants and Lifestyle Factors in Hypothyroidism: A Hospital-Based Cohort Study

Hypothyroidism is a prevalent endocrine disorder and is associated with a variety of metabolic disturbances. This study aimed to investigate the polygenic variants associated with hypothyroidism risk and the interaction of polygenic risk scores (PRS) with dietary patterns in influencing disease risk in 56,664 participants aged >40 in a hospital-based cohort. The participants were classified as having hypothyroidism (n = 870) diagnosed by a physician and no hypothyroidism (n = 55,794). Genetic variants associated with hypothyroidism were identified using a genome-wide association study (GWAS). Genetic variants interacting with each other were selected using a generalized multifactor dimensionality reduction analysis, and the PRS generated was evaluated for interaction with lifestyle parameters. Coffee, alcohol, meat intake, and a Korean balanced diet were inversely associated with hypothyroidism risk, as were selenium, copper, and manganese intakes. White blood cell (WBC) counts and serum alkaline phosphatase and triglyceride concentrations were positively associated with hypothyroidism risk, as were osteoporosis and thyroid cancer. The GMDR analysis generated a three-single nucleotide polymorphism (SNP) model comprising dual oxidase-1 (DUOX1)_rs1648314; thyroid-stimulating hormone receptor (TSHR)_rs75664963; and major histocompatibility complex, class-II, DQ Alpha-1 (HLA-DQA1)_rs17426593. The PRS derived from the three- and seven-SNP models were associated with a 2.11- and 2.32-fold increase in hypothyroidism risk, respectively. Furthermore, the PRS from the three-SNP model showed interactions with WBC counts, wherein the positive association with hypothyroidism risk was more pronounced in participants with low WBC counts than those with high WBC counts (≥4 × 109 /L). Dietary patterns, such as the plant-based diet (PBD) and the Western-style diet (WSD), along with smoking status, exhibited interactions with the PRS, influencing hypothyroidism risk. In participants with a high PRS, those in the high-PBD, low-WSD, and smoker groups had a higher proportion of hypothyroidism than those in the low-PBD, high-WSD, and non-smoker groups. In conclusion, genetic variants related to immunity and thyroid hormone secretion were linked to hypothyroidism risk, and their PRS interacted with PBD and WSD intake and smoking status. These results contribute to a better understanding of hypothyroidism and its prevention strategies for precision medicine intervention.

Investigation of the interaction between Genetic Risk Score (GRS) and fatty acid quality indices on mental health among overweight and obese women

BACKGROUND & AIMS

Mental disorders are associated with dietary fatty acids and genome-wide association studies have found multiple risk loci robustly related to depression, anxiety, and stress. The aim of this study is to investigate the interaction of genetic risk score (GRS) and dietary fat quality indices on mental health.

METHODS

This cross-sectional study included 279 overweight and obese women for N6/N3 ratio and 378 overweight and obese women for CSI aged 18-68 years. Using reliable and verified standard protocols, body composition, anthropometric indices, blood pressure, physical activity, and dietary fat quality were measured. Serum samples were used to determine biochemical tests. A genetic risk score (GRS) was calculated using the risk alleles of the three SNPs. A generalized linear model (GLM) was applied to assess the interactions between GRS and fat quality indices. Mental health was evaluated using Depression Anxiety Stress Scales (DASS-21).

RESULTS

The mean (± SD) age and BMI of our participants were 36.48 (8.45) and 30.73 (3.72) kg/m2 respectively. There was a marginally significant mean difference among tertiles of the CSI in terms of stress (P = 0.051), DASS-21 (P = 0.078) in the crude model. After adjusting for age, energy intake, physical activity and BMI in model 1, there was a positive interaction between GRS and T3 of N6/N3 ratio on anxiety (β = 0.91, CI = 0.08,1.75, P = 0.031), depression (β = 1.05, CI = 0.06,2.04, P = 0.037), DASS-21 (β = 2.22, CI= -0.31,4.75, P = 0.086).

CONCLUSION

Our findings indicate that higher ratio of N-6 to N-3 considering genetics were predictive of mental disorder in our population.

Interaction of environmental factors with the polygenic risk scores of thinness-related genes in preventing obesity risk in middle-aged adults: The KoGES

BACKGROUND

Some persons are genetically resistant to obesity, but only a few studies have evaluated thinness genes for preventing obesity. We aimed to investigate the association of polygenic variants with being underweight and their interaction with the lifestyles of middle-aged and elderly persons and identify potential new genetic approaches for managing body weight.

METHODS

In total, 58,701 participants aged 40-77 years were recruited from urban hospitals in Korea. Underweight (case) was defined as body mass index (BMI) < 18.5 kg m2 (n = 991) and normal weight (control, n = 21,921) was defined as 18.5 ≤ BMI < 23 kg m2 . A genome-wide association study was run to identify thinness-related single nucleotide polymorphisms (SNPs) after adjustment for compound factors using Gplink. The generalised multifactor dimensionality reduction program was used to identify the genetic variants with SNP-SNP interactions. The polygenic risk score (PRS) was calculated by summing up the number of risk alleles in each SNP and classifying them into low-, medium- and high-PRS.

RESULTS

The best model included the ANK2_rs7656666, CAST_rs28042, SLC1A3_rs928431867, CHST12_rs2906173, ALOX5_rs1051713, RGS6_rs17180754, ST8SIA5_rs79491311 and DCC_rs35721894 alleles. The participants with high-PRS had a lower BMI (p < 0.0001) than those with low-PRS and were 3.834 (2.58-5.70) times more likely to be underweight after multivariate adjustment (p < 0.001). The selected SNPs were correlated with each other and highly expressed in brain-related genes. The genes with minor alleles of CAST_rs28042 and CHST12_rs2906173 exhibited a higher expression frequency in brain-related tissues. PRS had significant interactions with protein, sodium, indigestible carbohydrates, calcium intake and exercise (p < 0.05), influencing the underweight state. People with a high-PRS were more underweight than those with low-PRS under high protein, sodium, high calcium, low indigestible carbohydrate intake and low exercise by 3.75, 3.88, 7.05, 3.18 and 3.80 times, respectively (p < 0.0001).

CONCLUSIONS

In conclusion, adults having a high-PRS were significantly correlated with being underweight, especially in combination with a particular nutritional status. These results show the potential for thinness genes to be applied to personalised nutrition for preventing obesity through targeted gene therapy.

Interaction of fatty acid quality indices and genes related to lipid homeostasis on mental health among overweight and obese women

The aim of this study is to investigate the interaction of fatty acid quality indices and genes related to lipid homeostasis on mental health among overweight and obese women. This cross-sectional study included 279 overweight and obese women for N6/N3 ratio and 378 overweight and obese women for CSI aged 18-58 years. Mental health were evaluated using Depression Anxiety Stress Scales (DASS-21). The anthropometric indices, biochemical parameters, body composition and dietary fat quality were measured. MC4R (rs17782313) and Caveolin-1 (CAV-1) (rs3807992) were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. The results of the study showed that after adjusting for age, energy intake, thyroid disease, physical activity, and BMI, a positive interaction between TC genotype of MC4R and CSI on depression (β = 0.39, CI = 0.12, 0.66, P = 0.004), and DASS-21 (β = 0.074, CI = 0.04, 1.44, P = 0.036). Also, there were a marginal significant interactions between AG genotype of CAV-1 and N6/N3 ratio on depression in adjustment model1 (β = 16.83, CI = - 0.19, 33.85, P = 0.053). Our findings showed that increasing adherence to fatty acid quality indices by considering genes related to lipid homeostasis was related to increasing depression in our population.

A Prediction Model for Osteoporosis Risk Using a Machine-Learning Approach and Its Validation in a Large Cohort

BACKGROUND

Osteoporosis develops in the elderly due to decreased bone mineral density (BMD), potentially increasing bone fracture risk. However, the BMD is not regularly measured in a clinical setting. This study aimed to develop a good prediction model for the osteoporosis risk using a machine learning (ML) approach in adults over 40 years in the Ansan/Anseong cohort and the association of predicted osteoporosis risk with a fracture in the Health Examinees (HEXA) cohort.

METHODS

The 109 demographic, anthropometric, biochemical, genetic, nutrient, and lifestyle variables of 8,842 participants were manually selected in an Ansan/Anseong cohort and included in the ML algorithm. The polygenic risk score (PRS) of osteoporosis was generated with a genome-wide association study and added for the genetic impact of osteoporosis. Osteoporosis was defined with < -2.5 T scores of the tibia or radius compared to people in their 20s-30s. They were divided randomly into the training (n = 7,074) and test (n = 1,768) sets-Pearson's correlation between the predicted osteoporosis risk and fracture in the HEXA cohort.

RESULTS

XGBoost, deep neural network, and random forest generated the prediction model with a high area under the curve (AUC, 0.86) of the receiver operating characteristic (ROC) with 10, 15, and 20 features; the prediction model by XGBoost had the highest AUC of ROC, high accuracy and k-fold values (> 0.85) in 15 features among seven ML approaches. The model included the genetic factor, genders, number of children and breastfed children, age, residence area, education, seasons to measure, height, smoking status, hormone replacement therapy, serum albumin, hip circumferences, vitamin B6 intake, and body weight. The prediction models for women alone were similar to those for both genders, with lower accuracy. When the prediction model was applied to the HEXA study, the correlation between the fracture incidence and predicted osteoporosis risk was significant but weak (r = 0.173, P < 0.001).

CONCLUSION

The prediction model for osteoporosis risk generated by XGBoost can be applied to estimate osteoporosis risk. The biomarkers can be considered for enhancing the prevention, detection, and early therapy of osteoporosis risk in Asians.

Lateral septum as a melanocortin downstream site in obesity development

The melanocortin pathway is well established to be critical for body-weight regulation in both rodents and humans. Despite extensive studies focusing on this pathway, the downstream brain sites that mediate its action are not clear. Here, we found that, among the known paraventricular hypothalamic (PVH) neuron groups, those expressing melanocortin receptors 4 (PVH^Mc4R) preferably project to the ventral part of the lateral septum (LSv), a brain region known to be involved in emotional behaviors. Photostimulation of PVH^Mc4R neuron terminals in the LSv reduces feeding and causes aversion, whereas deletion of Mc4Rs or disruption of glutamate release from LSv-projecting PVH neurons causes obesity. In addition, disruption of AMPA receptor function in PVH-projected LSv neurons causes obesity. Importantly, chronic inhibition of PVH- or PVH^Mc4R-projected LSv neurons causes obesity associated with reduced energy expenditure. Thus, the LSv functions as an important node in mediating melanocortin action on body-weight regulation.

The interaction between MC4R gene variant (rs17782313) and dominant dietary patterns on depression in obese and overweight women: a cross sectional study

BACKGROUND

Previous studies have shown that the minor allele (C allele) for melanocortin 4 receptor (MC4R) rs17782313 may be associated with depressed mood. Moreover, dietary patterns have potentially adverse effects on depression. This study investigates the interactions between the MC4R gene variant (rs17782313) and dietary patterns on depression among Iranian obese and overweight women.

METHODS

A total of 289 Iranian overweight and obese women, aged 18-50 years, were enrolled in this cross-sectional study. Biochemical, anthropometric, and body composition indices were assessed in all participants. Moreover, MC4R rs17782313, by the restriction fragment length polymorphism (PCR-RFLP) method, and depression, using the 21-item Depression Anxiety Stress Scales (DASS) questionnaire, were assessed. Food intakes were assessed by completing a 147-item semi-quantitative food frequency questionnaire (FFQ).

RESULTS

By the use of factor analysis, 2 major dietary patterns were extracted: healthy dietary pattern (HDP) and unhealthy dietary pattern (UDP). Binary logistic analysis showed that individuals with minor allele risk (CC) with high adherence to the unhealthy pattern increased odds for depression (OR: 8.77, 95%CI: -0.86-18.40, P: 0.07), after controlling for confounders. Also, a logical inverse relationship was observed between CT genotype and HDP on depression in the crude and adjusted models (OR: -0.56, 95% CI: -3.69-2.57, P: 0.72) (OR: -4.17, 95% CI: -9.28-0.94, P: 0.11), although this interaction was not statistically significant.

CONCLUSION

According to the above findings, adherence to unhealthy food intake pattern increases odds of depression in MC4R risk allele (C allele) carriers. To confirm these findings, more studies are needed in the form of clinical trials and prospective studies with higher sample sizes.

Association of Polygenic Variants Involved in Immunity and Inflammation with Duodenal Ulcer Risk and Their Interaction with Irregular Eating Habits

Genetic and environmental factors are associated with developing and progressing duodenal ulcer (DU) risk. However, the exact nature of the disease pathophysiology and the single nucleotide polymorphism (SNP)-lifestyle interaction has yet to be determined. The purpose of the present study was to examine the SNPs linked to DU risk and their interaction with lifestyles and diets in a large hospital-based cohort of Asians. Based on an earlier diagnosis, the participants were divided into the DU (case; n = 1088) and non-DU (control, n = 56,713) groups. The SNP associated with DU risk were obtained from a genome-wide association study (GWAS), and those promoted genetic impact with SNP-SNP interactions were identified with generalized multifactor dimensionality reduction analysis. The interaction between polygenic risk score (PRS) calculated from the selected genetic variants and nutrient were examined. They were related to actin modification, immune response, and cell migration by modulating leucine-rich repeats (LRR) domain binding, Shaffer interferon regulatory factor 4 (IRF4) targets in myeloma vs. mature B lymphocyte, and Reactome runt-related transcription factor 3 (RUNX3). Among the selected SNPs, rs11230563 (R225W) showed missense mutation and low binding affinity with different food components in the autodock analysis. Glycyrrhizin, physalin B, janthitrem F, and casuarinin lowered it in only wild CD6 protein but not in mutated CD6. Plastoquinone 8, solamargine, saponin D, and matesaponin 2 decreased energy binding affinity in mutated CD6 proteins. The PRS of the 5-SNP and 6-SNP models exhibited a positive association with DU risk (OR = 3.14). The PRS of the 5-SNP PRS model interacted with irregular eating habits and smoking status. In participants with irregular eating habits or smokers, DU incidence was much higher in the participants with high PRS than in those with low PRS. In conclusion, the genetic impact of DU risk was mainly in regulating immunity, inflammation, and actin modification. Adults who are genetically susceptible to DU need to eat regularly and to be non-smokers. The results could be applied to personalize nutrition.

Interaction between ultra-processed food intake and genetic risk score on mental health and sleep quality

PURPOSE

Mental health and sleep quality are associated with genetics and nutrient and energy intake. The present study examined the association between ultra-processed food (UPF) intake and genetic risk score (GRS) and their interactions on mental health and sleep quality in Iranian women.

METHODS

A cross-sectional study was conducted on 278 overweight and obese females aged between 18 and 56 years. According to the NOVA classification system, 37 food groups and beverages were collected using a 147-item semi-quantitative food frequency questionnaire (FFQ). The blood parameters of all participants were assessed. Mini-column kit (type G; Genall; Exgene) and the PCR-RFLP method were used to extract DNA and determine gene polymorphism, respectively. Three single nucleotide polymorphisms (SNPs), including Caveolin_1 (Cav_1), Melanocortin4 receptor (MC4R), and cryptochrome circadian regulator 1 (CRY1), were used to calculate GRS. The individual risk allele (0, 1, 2) for each SNP was calculated using the incremental genetic model.

RESULTS

After controlling for confounders, a significant interaction was found for depression (β = 0.026, 95% CI 0.003, 0.049, P = 0.028) and depression anxiety stress scales (DASS) score (β = 0.059, 95% CI 0.001, 0.117, P = 0.046) on the NOVA classification system and GRS.

CONCLUSIONS

The findings of this study showed a significant interaction between GRS and the NOVA classification system on mental disorders, including depression, DASS score and stress. There was also a significant relationship between the NOVA classification system and anxiety, DASS score, sleep quality and depression. Furthermore, a partially significant association was observed between GRS and stress.

LEVEL OF EVIDENCE

Level V, cross-sectional descriptive study.

In the context of the triple burden of malnutrition: A systematic review of gene-diet interactions and nutritional status

Genetic background interacts with dietary components to modulate nutritional health status. This study aimed to review the evidence for gene-diet interactions in all forms of malnutrition. A comprehensive systematic literature search was conducted through April 2021 to identify observational and intervention studies reporting the effects of gene-diet interactions in over-nutrition, under-nutrition and micronutrient status. Risk of publication bias was assessed using the Quality Criteria Checklist and a tool specifically designed for gene-diet interaction research. 167 studies from 27 populations were included. The majority of studies investigated single nucleotide polymorphisms (SNPs) in overnutrition (n = 158). Diets rich in whole grains, vegetables, fruits and low in total and saturated fats, such as Mediterranean and DASH diets, showed promising effects for reducing obesity risk among individuals who had higher genetic risk scores for obesity, particularly the risk alleles carriers of FTO rs9939609, rs1121980 and rs1421085. Other SNPs in MC4R, PPARG and APOA5 genes were also commonly studied for interaction with diet on overnutrition though findings were inconclusive. Only limited data were found related to undernutrition (n = 1) and micronutrient status (n = 9). The findings on gene-diet interactions in this review highlight the importance of personalized nutrition, and more research on undernutrition and micronutrient status is warranted.

Association and interaction of the MC4R rs17782313 polymorphism with plasma ghrelin, GLP-1, cortisol, food intake and eating behaviors in overweight/obese Iranian adults

BACKGROUND

Recent studies have shown that obesity is largely influenced by heredity and created by the interactions between several genes and environmental and behavioral factors. This study aimed to examine association between variant rs17782313 near melanocortin-4 receptor (MC4R) gene and behavioral and hormonal factors then evaluated interactions between variant MC4R rs17782313 with behavioral and hormonal factors on obesity.

METHODS

This cross-sectional study included 403 subjects, overweight and/or obesity, aged 20-50 years from Iran. The MC4R rs17782313 data were measured by the PCR-RFLP method. Dietary intake, physical activity, stress, anxiety, depression, appetite and emotional eating were assessed by using validated questionnaires. Ghrelin, glucagon-like peptide-1 and cortisol were measured by radioimmunoassay in plasma samples. Participants were also divided into three groups based on rs17782313 genotype and BMI.

RESULTS

After adjustment for age, gender, energy intake and PA, significant associations were observed between food intake, appetite, emotional eating, stress and physical activity with MC4R rs17782313 (p ˂0.05). Also, significant interactions were observed between fat intake (p-interaction = 0.002), protein intake (p-interaction = 0.01), energy intake (p-interaction = 0.01), emotional eating (p-interaction = 0.02), appetite (p-interaction = 0.04), stress (p-interaction = 0.04), ghrelin (p-interaction = 0.03), cortisol (p-interaction = 0.04) and physical activity (p-interaction = 0.04) and MC4R rs17782313 in terms of BMI.

CONCLUSION

Interactions between the CC genotype and high intakes of fat and energy, emotional eating, high appetite, and too much stress with high levels of cortisol and ghrelin probably can have an effect on BMI in overweight/obese subjects.

Association of Polygenic Variants with Type 2 Diabetes Risk and Their Interaction with Lifestyles in Asians

Over the last several decades, there has been a considerable growth in type 2 diabetes (T2DM) in Asians. A pathophysiological mechanism in Asian T2DM is closely linked to low insulin secretion, β-cell mass, and inability to compensate for insulin resistance. We hypothesized that genetic variants associated with lower β-cell mass and function and their combination with unhealthy lifestyle factors significantly raise T2DM risk among Asians. This hypothesis was explored with participants aged over 40. Participants were categorized into T2DM (case; n = 5383) and control (n = 53,318) groups. The genetic variants associated with a higher risk of T2DM were selected from a genome-wide association study in a city hospital-based cohort, and they were confirmed with a replicate study in Ansan/Ansung plus rural cohorts. The interacted genetic variants were identified with generalized multifactor dimensionality reduction analysis, and the polygenic risk score (PRS)-nutrient interactions were examined. The 8-SNP model was positively associated with T2DM risk by about 10 times, exhibiting a higher association than the 20-SNP model, including all T2DM-linked SNPs with p < 5 × 10−6. The SNPs in the models were primarily involved in pancreatic β-cell growth and survival. The PRS of the 8-SNP model interacted with three lifestyle factors: energy intake based on the estimated energy requirement (EER), Western-style diet (WSD), and smoking status. Fasting serum glucose concentrations were much higher in the participants with High-PRS in rather low EER intake and high-WSD compared to the High-EER and Low-WSD, respectively. They were shown to be higher in the participants with High-PRS in smokers than in non-smokers. In conclusion, the genetic impact of T2DM risk was mainly involved with regulating pancreatic β-cell mass and function, and the PRS interacted with lifestyles. These results highlight the interaction between genetic impacts and lifestyles in precision nutrition.

Association Between Korean-Style Balanced Diet and Risk of Abdominal Obesity in Korean Adults: An Analysis Using KNHANES-VI (2013-2016)

Abdominal obesity is a critical factor for metabolic diseases, and specific eating patterns such as the Mediterranean diet help prevent metabolic diseases. This study aimed to investigate the association between the modified Korean health eating index (MKHEI), including a Korean-balanced diet, and abdominal obesity risk according to genders in adults aged 20-64 years (4,886 males and 7,431 females), using the Korea National Health and Nutrition Examination Survey VI (2013-2016). Adjusted means and 95% confidence intervals of MKHEI scores and nutrient intake estimated using the 24-h recall method were calculated according to abdominal obesity (waist circumference ≥90 cm for men and ≥85 cm for women) after adjusting for age, residence area, region, education, income, drinking status, smoking status, marital status, and exercise. Adjusted odds ratios (ORs) for abdominal obesity were measured according to MKHEI tertiles using logistic regression analysis while controlling for covariates. Individuals aged >50 years, married, below high school, lower-income, heavy alcohol drinkers, past and current smokers, and males living in the southern areas had a higher risk of abdominal obesity. In both genders, the scores of all MKHEI components were lower in the abdominal obesity group (n = 2,895) than in the control group (n = 9,422). Further, the scores of fruits with and without fruit juice and those of beans, including fermented beans, were lower in the abdominal obesity group only in females but not in males. Further, the scores of fast foods were higher in the abdominal obesity group than in the control group only in females. After adjusting for covariates, the adjusted OR for abdominal obesity was inversely associated with Korean balanced diet (KBD) related to KHEI scores. Unlike KBD, MKHEI of Western-style diet was not associated with abdominal obesity in either gender. In conclusion, KBD can lower the risk of abdominal obesity in females and should thus be recommended to prevent abdominal obesity.

Development and Validation of an Insulin Resistance Predicting Model Using a Machine-Learning Approach in a Population-Based Cohort in Korea

Background: Insulin resistance is a common etiology of metabolic syndrome, but receiver operating characteristic (ROC) curve analysis shows a weak association in Koreans. Using a machine learning (ML) approach, we aimed to generate the best model for predicting insulin resistance in Korean adults aged > 40 of the Ansan/Ansung cohort using a machine learning (ML) approach. Methods: The demographic, anthropometric, biochemical, genetic, nutrient, and lifestyle variables of 8842 participants were included. The polygenetic risk scores (PRS) generated by a genome-wide association study were added to represent the genetic impact of insulin resistance. They were divided randomly into the training (n = 7037) and test (n = 1769) sets. Potentially important features were selected in the highest area under the curve (AUC) of the ROC curve from 99 features using seven different ML algorithms. The AUC target was ≥0.85 for the best prediction of insulin resistance with the lowest number of features. Results: The cutoff of insulin resistance defined with HOMA-IR was 2.31 using logistic regression before conducting ML. XGBoost and logistic regression algorithms generated the highest AUC (0.86) of the prediction models using 99 features, while the random forest algorithm generated a model with 0.82 AUC. These models showed high accuracy and k-fold values (>0.85). The prediction model containing 15 features had the highest AUC of the ROC curve in XGBoost and random forest algorithms. PRS was one of 15 features. The final prediction models for insulin resistance were generated with the same nine features in the XGBoost (AUC = 0.86), random forest (AUC = 0.84), and artificial neural network (AUC = 0.86) algorithms. The model included the fasting serum glucose, ALT, total bilirubin, HDL concentrations, waist circumference, body fat, pulse, season to enroll in the study, and gender. Conclusion: The liver function, regular pulse checking, and seasonal variation in addition to metabolic syndrome components should be considered to predict insulin resistance in Koreans aged over 40 years.

Nutrigenetics and nutrigenomics-A personalized approach to nutrition

The prevalence of non-communicable diseases has been on an upward trajectory for some time and this puts an enormous burden on the healthcare expenditure. Lifestyle modifications including dietary interventions hold an immense promise to manage and prevent these diseases. Recent advances in genomic research provide evidence that focussing these efforts on individual variations in abilities to metabolize nutrients (nutrigenetics) and exploring the role of dietary compounds on gene expression (nutrigenomics and nutri-epigenomics) can lead to more meaningful personalized dietary strategies to promote optimal health. This chapter aims to provide examples on these gene-diet interactions at multiple levels to support the need of embedding targeted dietary interventions as a way forward to prevent, avoid and manage diseases.

A Positive Association of Overactivated Immunity with Metabolic Syndrome Risk and Mitigation of Its Association by a Plant-Based Diet and Physical Activity in a Large Cohort Study

The association between immunity and metabolic syndrome (MetS) has been studied, but its interaction with lifestyles remains unclear. We studied their association and interactions with lifestyles in 40,768 adults aged over 40 years from a large-scale, hospital-based cohort study collected during 2010-2013. White blood cell counts (WBC) and serum C-reactive protein concentrations (CRP) were used as indexes of immune status. The participants were categorized into four groups by the cutoff points of 6.2 × 10⁹/L WBC(L-WBC) and <0.5 mg/dL CRP(L-CRP): L-WBC+L-CRP(n = 25,604), H-WBC+L-CRP(n = 13,880), L-WBC+H-CRP(n = 464), and H-WBC+H-CRP(n = 820). The participants in the H-WBC+L-CRP were younger and had higher numbers of males than the L-WBC+L-CRP. MetS risk was higher by 1.75- and 1.86-fold in the H-WBC+L-CRP and H-WBC+H-CRP, respectively, than the L-WBC+L-CRP. MetS components, including plasma glucose and triglyceride concentrations, and SBP were elevated in H-WBC+L-CRP and H-WBC+H-CRP compared with L-WBC+L-CR+P. The risk of hyperglycemia and high HbA1c was the highest in the H-WBC+H-CRP among all groups. Areas of WBC counts and serum CRP concentrations were 0.637 and 0.672, respectively, in the receiver operating characteristic curve. Daily intake of energy, carbohydrate, protein, and fat was not significantly different in the groups based on WBC counts and CRP. However, a plant-based diet (PBD), physical activity, and non-smoking were related to lowering WBC counts and CRP, but a Western-style diet was linked to elevating CRP. A high PBD intake and smoking status interacted with immunity to influence MetS risk: a low PBD and current smoking were associated with a higher MetS risk in the H-WBC+H-CRP. In conclusion, overactivated immunity determined by CRP and WBC was associated with MetS risk. Behavior modification with PBD and physical activity might be related to immunity regulation.

A Western-style diet interacts with genetic variants of the LDL receptor to hyper-LDL cholesterolemia in Korean adults

OBJECTIVE

To evaluate the association of genetic risk scores (GRS) of LDLR, APOB and proprotein convertase subtilisin-kexin type 9 (PCSK9) SNP and plasma LDL concentrations and to identify lifestyle interactions with the GRS in Korean middle-aged adults.

DESIGN

Korean genome and epidemiology study (KoGES) was conducted to determine genetic variants and lifestyle factors, including nutrient intakes, in a retrospective hospital-based city cohort conducted by the Korean Center for Disease and Control during 2004-2013.

SETTINGS

Hospitals in Korea.

PARTICIPANTS

Adults aged 40-77 years (n 28 445) without serious diseases.

RESULTS

Subjects with the major alleles (risk allele) of LDLR rs1433099 and rs11557092, APOB rs13306194 and PCSK9 rs11583723 had higher plasma LDL concentration by 1·20-folds than those with the minor alleles. Subjects with High-GRS (major alleles) of the four SNP had higher adjusted OR for plasma total and LDL-cholesterol and TAG concentrations by 1·24-, 1·203- and 1·167-folds, respectively, but not HDL-cholesterol, than those with Low-GRS. Western-style flour-rich dietary patterns, but not balanced Korean-style and rice-based dietary patterns, had interactions with GRS to increase plasma LDL concentrations. Daily energy intake also interacted with GRS. In the high intake of Western-style flour-rich dietary patterns, carriers with High-GRS had much higher plasma LDL concentrations than the Low-GRS. With high energy intake, carriers with High-GRS had much higher plasma LDL concentrations than those with Low-GRS.

CONCLUSIONS

Adults with major alleles of four SNP are recommended to have low-energy intakes with a balanced Korean diet need to avoid high-energy intakes especially with Western-style flour-rich diet patterns.

Effect of interaction between obesity-promoting genetic variants and behavioral factors on the risk of obese phenotypes

The studies investigating gene-gene and gene-environment (or gene-behavior) interactions provide valuable insight into the pathomechanisms underlying obese phenotypes. The Pakistani population due to its unique characteristics offers numerous advantages for conducting such studies. In this view, the current study was undertaken to examine the effects of gene-gene and gene-environment/behavior interactions on the risk of obesity in a sample of Pakistani population. A total of 578 adult participants including 290 overweight/obese cases and 288 normal-weight controls were involved. The five key obesity-associated genetic variants namely MC4R rs17782313, BDNF rs6265, FTO rs1421085, TMEM18 rs7561317, and NEGR1 rs2815752 were genotyped using the TaqMan allelic discrimination assays. The data related to behavioral factors, such as eating pattern, diet consciousness, the tendency toward fat-dense food (TFDF), sleep duration, sleep-wake cycle (SWC), shift work (SW), and physical activity levels were collected via a questionnaire. Gene-gene and gene-behavior interactions were analyzed by multifactor dimensionality reduction and linear regression, respectively. In our study, only TMEM18 rs7561317 was found to be significantly associated with anthropometric traits with no significant effect of gene-gene interactions were observed on obesity-related phenotypes. However, the genetic variants were found to interact with the behavioral factors to significantly influence various obesity-related anthropometric traits including BMI, waist circumference, hip circumference, waist-to-hip ratio, waist-to-height ratio, and percentage of body fat. In conclusion, the interaction between genetic architecture and behavior/environment determines the outcome of obesity-related anthropometric phenotypes. Thus, gene-environment/behavior interaction studies should be promoted to explore the risk of complex and multifactorial disorders, such as obesity.

Associations of Polygenetic Variants at the 11q23 Locus and Their Interactions with Macronutrient Intake for the Risk of 3GO, a Combination of Hypertension, Hyperglycemia, and Dyslipidemia

3GO is a condition in which hypertension, hyperglycemia, and dyslipidemia co-occur, and these conditions are related to each other and genetic and environmental factors. We hypothesized that common genetic variants and their interactions with lifestyles influenced 3GO risk. We aimed to explore common genetic variants to affect 3GO risk and their haplotype interaction with lifestyles in a city hospital-based cohort in 58,701 Koreans > 40 years. 3GO was defined as SBP ≥ 140 mmHg and DBP ≥ 90 mmHg for hypertension, fasting blood glucose ≥ 126 mg/dL for hyperglycemia, and LDL ≥ 160 mg/dL or HDL ≤ 40 mg/dL, or triglyceride ≥ 200 mg/dL for dyslipidemia. Haplotypes were generated by genetic variants selected from genome-wide association study ((GWAS) an observational study of the genetic variation of the whole genome in different individuals, used to see if any variation is related to traits) after adjusting for age, sex, area of residence, and body mass index (BMI). Nutrient intakes were assessed using food frequency questionnaires. Interactions between haplotype and lifestyles and 3GO risk were investigated. Parameters related to metabolic syndrome were significantly different in the 0GO, 1-2GO, and 3GO groups, that is, groups of individuals with none, one to two, or all three of the components of 3GO. At the 11q23 locus, KCNQ1_rs2237892, ZPR1_rs2075291, APOA5_rs662799, APOA1_rs5072, and SIK3_rs151139277, influenced 3GO risk, and the minor alleles of their haplotype had a 3GO risk 3.23 times higher than the major alleles. For subjects with a high energy intake, the 3GO risk of the minor alleles was significantly higher than that of the major alleles (OR = 3.230, 95% confidence interval (CI) = 2.062~5.061, p < 0.001). BMI, HbA1c, SBP, and serum concentrations of glucose, HDL, and triglyceride were significantly higher for the minor allele than the major alleles (p < 0.001). The haplotype interacted with the intakes of protein (p = 0.033), digestible carbohydrate (p = 0.012), fat (p = 0.008), and undigestible carbohydrates (p = 0.015) to increase 3GO risk. An interaction was also observed between smoking and the haplotype (p = 0.007). The minor allele effects on 3GO incidence were higher in the high digestible carbohydrate intake and smoking groups. By contrast, the minor allele impacts on 3GO frequencies were much higher in the low intake of undigestible carbohydrates, protein, and fat. In conclusion, people who carry a minor allele of the 11q23 locus haplotype should avoid smoking and replace digestible carbohydrate intake with consuming high-quality protein, healthy fat, and undigestible carbohydrates.

Statistical and Machine-Learning Analyses in Nutritional Genomics Studies

Nutritional compounds may have an influence on different OMICs levels, including genomics, epigenomics, transcriptomics, proteomics, metabolomics, and metagenomics. The integration of OMICs data is challenging but may provide new knowledge to explain the mechanisms involved in the metabolism of nutrients and diseases. Traditional statistical analyses play an important role in description and data association; however, these statistical procedures are not sufficiently enough powered to interpret the large integrated multiple OMICs (multi-OMICS) datasets. Machine learning (ML) approaches can play a major role in the interpretation of multi-OMICS in nutrition research. Specifically, ML can be used for data mining, sample clustering, and classification to produce predictive models and algorithms for integration of multi-OMICs in response to dietary intake. The objective of this review was to investigate the strategies used for the analysis of multi-OMICs data in nutrition studies. Sixteen recent studies aimed to understand the association between dietary intake and multi-OMICs data are summarized. Multivariate analysis in multi-OMICs nutrition studies is used more commonly for analyses. Overall, as nutrition research incorporated multi-OMICs data, the use of novel approaches of analysis such as ML needs to complement the traditional statistical analyses to fully explain the impact of nutrition on health and disease.

Dietary patterns interact with the variations of 18q21.23 rs17782313 locus on regulation of hypothalamic-pituitary axis hormones and cardio-metabolic risk factors in obesity

BACKGROUND

Evidence shows the role of polymorphisms in rs17782313 MC4R gene with increased risk of obesity in Asians adult. In the current report, we investigated the interaction between rs17782313 MC4R gene and major dietary patterns on α-melanocyte stimulating hormone (α-MSH), Agouti-related peptide (AgRP), serum lipids and blood pressure among obese individuals.

METHODS

This cross-sectional study was performed in 288 obese adults between 20 and 50 years of age. Anthropometric measurements and biochemical assays were conducted with standard methods. To evaluate appetite, the Visual Analogue Scale (VAS) was used. Dietary patterns were obtained by principal component analysis (PCA). Genotyping of rs17782313 was assessed by restriction fragment length polymorphism (PCR-RFLP) method.

RESULTS

Three major dietary patterns were extracted: Prudent Dietary Pattern (PDP), Legume Dietary Pattern (LDP) and Mixed Dietary Pattern (MDP). Higher PDP score was associated with reduced SBP and insulin concentration while highest MDP score was associated with lower TG concentration (P < 0.05). Significant interactions were observed between higher adherence to PDP and rs17782313 CC genotype on increased SBP (P_Interaction = 0.04), serum insulin (P_Interaction = 0.05) and AgRP (P_Interaction = 0.03) and also between higher adherence to MDP and CC genotype of rs17782313 on reduced serum TG (P = 0.03).

CONCLUSIONS

The findings of the current study showed that being on CC genotype of rs17782313 polymorphism made obese individuals more prone to have higher SBP, insulin and AgRP even in highest adherence to PDP. However, adherence to MDP could attenuate the risky effects of being on CC genotype of rs17782313 by reducing serum TG concentrations.

LEVEL OF EVIDENCE

Level V, cross-sectional descriptive study.

Associations between metabolic syndrome and urinary Na-to-K ratio and glomerular filtration rate in middle-aged adults regardless of Na and K intakes

BACKGROUND

Intake of Na-to-K ratio (I-Na/K), urinary Na-to-K ratio (U-Na/K), and estimated glomerular filtration rate (GFR) have been reported to be risk factors of metabolic syndrome (MetS), but results are inconsistent. We examined the hypothesis that U-Na/K, GFR, and a preference for salty foods are associated with MetS risk and the hypothesis in 8540 adults aged over 40 years without chronic kidney disease.

METHODS

Participants were categorized using a U-Na/K of < 2.1 (low-U-Na/k) and a GFR of < 60 mL/min (low-GFR). A GFR of 60-90 mL/min was considered as a normal level, since it is a normal or marginal disease state. Correlations and associations were determined using Pearson's correlation coefficients and logistic regression analysis after adjusting for covariates related to MetS.

RESULTS

U-Na/K, but not I-Na/K, was positively correlated with blood pressure (r² = 0.20, P < 0.0001). The GFR was negatively correlated with age, gender, HOMA-B, and MetS (r² = - 0.14 to - 0.595, P < 0.0001), and positively correlated with education, current smoking, and alcohol intake (r² = 0.21 to 0.40, P < 0.0001). MetS risk had a positive association with the following combinations with low-U-Na/K + low-GFR, high-U-Na/K + high-GFR, and high-U-Na/K +low-GFR by 1.830-, 3.182-, and 3.696-fold, respectively, as compared with low-U-Na/K + high-GFR. Risks of the MetS components (abdominal obesity, hypertriglyceridemia, hypo-HDL-cholesterolemia, hypertension, and hyperglycemia) were similarly associated with U-Na/K and GFR, though hypertension had the strongest association. Hypertension risk had positive associations with low-U-Na/K + low-GFR, high-U-Na/K + high-GFR, and high-U-Na/K + low-GFR by 1.526-, 14.06-, and 7.079-fold, respectively, as compared with low-U-Na/K + high-GFR.

CONCLUSION

MetS risk was found to be associated with U-Na/K and GFR regardless of I-Na/K. Women need to maintain a high GFR to reduce the MetS risk, especially the risk of hypertension.

The interaction between dietary Non-Enzymatic Antioxidant Capacity (NEAC) with variants of Melanocortin-4 receptor (MC4R) 18q21.23-rs17782313 locus on hypothalamic hormones and cardio-metabolic risk factors in obese individuals from Iran

Background: In the current study, we aimed to evaluate the interaction between dietary Non-Enzymatic Antioxidant Capacity (NEAC) and rs17782313 polymorphism on hypothalamic hormones and cardio-metabolic risk factors. Methods: A total of 287 subjects (aged 20-50 years, 147 males and 140 females) enrolled in the cross-sectional study. Dietary NEAC was assessed using databases of NEAC measurements compiled from outcomes for three different analyses: oxygen radical absorbance capacity (ORAC), ferric reducing-antioxidant power (FRAP), and total radical-trapping antioxidant parameter (TRAP) and genotyping for the near MC4R rs17782313 was carried out by Polymerase chain reaction-restriction fragments length polymorphism (PCR-RFLP) method. Results: The significant interactions were found between adherence to the dietary NEAC and MC4R rs17782313 in relation to high-density lipoprotein-cholesterol (HDL-C), glucose, α-melanocyte stimulating hormone (α-MSH), insulin and quantitative insulin sensitivity check index (QUICKI) (P _Interaction = 0.03, 0.01, 0.04, 0.04 and 0.04, respectively). In homozygous subjects for the minor allele, the serum insulin level and QUICKI in participants with the highest adherence to TRAP were significantly higher than those with the lowest adherence (p < 0.001). There was a significant inverse association between high ORAC score and risk of metabolic syndrome even after adjusting for potential confounders (OR: 0.33; 95%CI:0.13-0.81) and also a significant inverse association between high NEAC (ORAC, FRAP and TRAP assays) score and high triglyceride (TG) level was found in obese adults. Conclusion: In conclusion, our study found for the first time that the NEAC significantly interacts with the rs17782313 genotypes to influence several metabolic risk factors in obesity.

The interaction between dietary patterns and melanocortin-4 receptor polymorphisms in relation to obesity phenotypes

INTRODUCTION

Data shows that interactions between dietary factors and genetic variants can modulate the association of polymorphisms such as the Melanocortin-4 receptor (MC4R) gene with obesity. Considering the limited data available on this topic we aimed to investigate interactions between dietary patterns (DPs) and MC4R polymorphisms in relation to obesity phenotypes.

METHODS

This cohort study was performed in the framework of Tehran Lipid and Glucose Study; for eligible participants in this study (n=3850), the median follow-up was 4 years. DPs were determined using factor analysis. The genotypes of polymorphisms (17782313rs and 12970134rs) were identified and their interaction with DPs were assessed in relation to incidence of obesity phenotypes including central obesity, general obesity and visceral adiposity dysfunction.

RESULTS

The mean age of participants (62.5% females) were 37.0±13.7 years. Two main DPs (healthy and unhealthy) were extracted. C-allele carriers of rs17782313 in higher quartiles of the healthy DP score had a significant decrease in the incidence of general obesity, compared to those who had the TT genotype (HR=0.61, 95% CI=0.42-0.89, P interaction=0.01). For rs12970134 A-allele carriers, subjects in the second compared to the first quartile of the healthy DP score, had a significant decrease in the incidence of general obesity (HR=0.68, 95% CI=0.46-0.99). There were no significant interaction between DPs and MC4R variants in relation to other obesity phenotypes.

CONCLUSION

Our results indicate that the healthy DP could interact with rs17782313 in relation to incidence of general obesity.

Depression increases the genetic susceptibility to high body mass index: Evidence from UK Biobank

BACKGROUND

This study aimed to explore the association between depression and body mass index (BMI), and to investigate whether genetic susceptibility to high BMI is different among individuals with or without depression.

METHODS

We used data on 251,125 individuals of white British ancestry from the UK Biobank. We conducted Mendelian randomization (MR) analysis to test for a causal association between depression and BMI using a major depressive disorder (MDD)-related genetic risk score (GRSMDD ) as an instrument for depression. We also examined whether depression modifies genetic susceptibility to high BMI, by investigating the interaction between depression and the BMI-related GRSBMI .

RESULTS

We found observational and genetic evidence for an association between depression and BMI (MR beta: 0.09, 95% confidence interval [CI] 0.04-0.13). Further, the contribution of genetic risk to high BMI was higher among individuals with depression compared to controls. Carrying 10 additional BMI increasing alleles was associated with 0.24 standard deviation (SD; 95%CI 0.23-0.25) higher BMI among depressed individuals compared to 0.20 SD (95%CI 0.19-0.21) higher in controls, which corresponds to 3.4 kg and 2.8 kg extra weight for an individual of average height. Amongst the individual loci, the evidence for interaction was most notable for a variant near MC4R, a gene known to affect both appetite regulation and the hypothalamic-pituitary adrenal axis (pinteraction  = 5.7 × 10-5 ).

CONCLUSION

Genetic predisposition to high BMI was higher among depressed than to nondepressed individuals. This study provides support for a possible role of MC4R in the link between depression and obesity.

Subcutaneous fat mass is associated with genetic risk scores related to proinflammatory cytokine signaling and interact with physical activity in middle-aged obese adults

Background and aims

Subcutaneous fat mass is negatively correlated with atherogenic risk factors, but its putative benefits remain controversial. We hypothesized that genetic variants that influence subcutaneous fat mass would modulate lipid and glucose metabolism and have interactions with lifestyles in Korean middle-aged adults with high visceral fat.

Materials and methods

Subcutaneous fat mass was categorized by dividing the average of subscapular skin-fold thickness by BMI and its cutoff point was 1.2. Waist circumferences were used for representing visceral fat mass with Asian cutoff points. GWAS of subjects aged 40–65 years with high visceral fat (n = 3303) were conducted and the best gene-gene interactions from the genetic variants related to subcutaneous fat were selected and explored using the generalized multifactor dimensionality reduction. Genetic risk scores (GRS) were calculated by weighted GRS that was divided into low, medium and high groups.

Results

Subjects with high subcutaneous fat did not have dyslipidemia compared with those with low subcutaneous fat, although both subject groups had similar amounts of total fat. The best model to influence subcutaneous fat included IL17A_rs4711998, ADCY2_rs326149, ESRRG_rs4846514, CYFIP2_rs733730, TCF7L2_rs7917983, ZNF766_rs41497444 and TGFBR3_rs7526590. The odds ratio (OR) for increasing subcutaneous fat was higher by 2.232 folds in the high-GRS group, after adjusting for covariates. However, total and LDL cholesterol, triglyceride and C-reactive protein concentrations in the circulation were not associated with GRS. Subjects with high-GRS had higher serum HDL cholesterol levels than those with low-GRS. Physical activity and GRS had an interaction with subcutaneous fat. In subjects with low physical activity, the odds ratio for high subcutaneous fat increased by 2.232, but subcutaneous fat deposition was not affected in the high-GRS group with high physical activity.

Conclusion

Obese adults with high-GRS had more subcutaneous fat, but they did not show more dyslipidemia and inflammation compared to low-GRS. High physical activity prevented subcutaneous fat deposition in subjects with high GRS for subcutaneous fat.

Sex-dependent effects of MC4R genotype on HPA axis tone: implications for stress-associated cardiometabolic disease

The melanocortin-4 receptor (MC4R) facilitates hypothalamic-pituitary-adrenocortical (HPA) axis responses to acute stress in male rodents and is a well known to regulator of energy balance. Mutations in the MC4R is the most common monogenic cause of obesity in humans and has been associated with sex-specific effects, but whether stress regulation by the MC4R is sex-dependent, and whether the MC4R facilitates HPA responses to chronic stress, is unknown. We hypothesized that MC4R-signaling contributes to HPA axis dysregulation and metabolic pathophysiology following chronic stress exposure. We measured changes in energy balance, HPA axis tone, and vascular remodeling during chronic variable stress (CVS) in male and female rats with MC4R loss-of-function. Rats were placed into three groups (n = 9-18/genotype/sex) and half of each group was subjected to CVS for 30 days or were non-stressed littermate controls. All rats underwent an acute restraint stress challenge on Day 30. Rats were euthanized on Day 31, adrenals collected for weight, and descending aortas fixed for morphological indices of vascular pathophysiology. We observed a marked interaction between Mc4r genotype and sex for basal HPA axis tone and acute stress responsivity. MC4R loss-of-function blunted both endpoints in males but exaggerated them in females. Contrary to our hypothesis, Mc4r genotype had no effect on either HPA axis responses or metabolic responses to chronic stress. Heightened stress reactivity of females with MC4R mutations suggests a possible mechanism for the sex-dependent effects associated with this mutation in humans and highlights how stress may differentially regulate metabolism in males and females. Lay summary The hypothalamic melanocortin system is an important regulator of energy balance and stress responses. Here, we report a sex-difference in the stress reactivity of rats with a mutation in this system. Our findings highlight how stress may regulate metabolism differently in males and females and may provide insight into sex-differences associated with this mutation in humans.

Evaluation of FTO rs9939609 and MC4R rs17782313 Polymorphisms as Prognostic Biomarkers of Obesity: A Population-based Cross-sectional Study

Objectives

Obesity is a significant risk factor for a number of chronic diseases, including diabetes, cardiovascular diseases, and cancer. Obesity usually results from a combination of causes and contributing factors, including genetics and lifestyle choices. Many studies have shown an association of single nucleotide polymorphisms (SNPs) in the fat mass and obesity-associated (FTO) and the melanocortin-4 receptor (MC4R) genes with body mass index (BMI). Therefore, recognizing the main genes and their relevant genetic variants will aid prediction of obesity risk. The aim of our study was to investigate the frequency of rs9939609 and rs17782313 polymorphisms in FTO and MC4R genes in an Iranian population.

Methods

We enrolled 130 obese patients and 83 healthy weight controls and calculated their BMI. Genomic DNA was extracted from peripheral blood and the frequency of rs9939609 and rs17782313 polymorphisms in FTO and MC4R genes was determined using the tetra-primer amplification refractory mutation system-polymerase chain reaction (ARMS-PCR).

Results

Significant associations were found between FTO rs9939609 and BMI. Where homozygous risk allele carriers (A-A) have significant higher odds ratio (OR) of being obese than individuals with normal BMI (OR = 6.927, p < 0.005, 95% confidence interval (CI): 3.48–13.78). No significant correlation between MC4R rs17782313 and obesity were observed when compared to healthy weight individuals. Although subjects with C-C genotype had higher odds of obesity (OR = 1.889, p = 0.077, 95%CI: 0.92–3.84).

Conclusions

This study shows a relationship between FTO polymorphism and increased BMI, therefore, SNP in the FTO gene influence changes in BMI and can be considered a prognostic marker of obesity risk.

Searching for Factors Raising the Incidence of Metabolic Syndrome Among 45-60-Year-Old Women

Metabolic syndrome is an increasing health problem, whose pathogenesis may be associated with genetic factors. The main purpose of our study was to assess relationships between MetS and the presence of the FTO rs9939609, the MC4R rs17782313, and the PPAR-γ rs1801282 polymorphisms in 45-60-year-old women. The study included patients from the general population of the Westpomeranian Province (Poland). The mean age was 54.3 ± 4.2 years. The research procedure involved taking structured history, physical examination, anthropometric measurements, and collecting blood for biochemical and genetic analysis. The patients who met the diagnostic criteria for MetS constituted 38.35% of all participants (sample size: 425 patients). The comparison of blood biochemical parameters revealed numerous differences between the women with MetS and those from the control group. Genetic analysis demonstrated that the T allele of the FTO gene was a factor substantially decreasing the incidence of MetS in the study sample (ORT vs. A = 0.734; 95% CI: 0.555 - 0.970; p < 0.05). Other polymorphisms were not directly related to MetS incidence.

CONCLUSIONS

1. MetS-related abnormalities are widespread in the population of 45-60-year-old Polish women. Those most common are the elevated serum total cholesterol and LDL levels, increased insulin resistance and BMI scores, as well as visceral obesity. 2. No direct relationships were demonstrated between MetS and the gene polymorphisms analyzed in our study except for the FTO rs9939609, whose A allele and A/A genotype seemed to predispose to metabolic disorders.

Zinc transporter SLC39A11 polymorphisms are associated with chronic gastritis in the Korean population: the possible effect on spicy food intake

Herein, we hypothesized that ZIP11 variants would be important risk factors for chronic gastritis and that there would be an interaction effect of the relationship between their variants and spicy food intake on the development of chronic gastritis. Participants in this cross-sectional study (n = 3882 + 252) were recruited from a cohort of the Korean Genome and Epidemiology Study in 2001. Age, sex, education, smoking and drinking status, exercise, stress, and income level of all participants were determined by a questionnaire. Demographic and anthropometric data were collected. Fasting blood samples were collected to determine the serum levels of glucose, insulin, total bilirubin, total cholesterol, high-density lipoprotein cholesterol, and triglycerides. The presence of chronic gastritis was defined as a confirmed diagnosis by a physician. Food consumption was determined using a semiquantitative food frequency questionnaire. We found 8 different single nucleotide polymorphisms (SNPs) that are significantly different between subjects without gastritis and those with gastritis. Of these 8 SNPs, 3 SNP (rs17183225 [C/T], rs17780814 [A/C], and rs17780820 [A/G]) are closely located in the intronic region of zinc transporter SLC39A11, commonly known as ZIP11, and show linkage disequilibrium (D' = 1.0). We also found that participants with (TCA + TCG) haplotype of ZIP11 at high levels of dietary intake of spicy foods show a significantly increasing tendency in the odds of having chronic gastritis when compared with those with CAA haplotype (odds ratio, 2.620; 95% confidence interval, 1.207-5.689). The data indicate positive associations between higher meal frequency and lower spicy food preference and gastritis. In conclusion, we found that zinc transporter gene ZIP11 is associated with chronic gastritis in the Korean population and it may interact with spicy food, which suggests ZIP11 as a therapeutic target for precision nutrition.

Associations between obesity candidate gene polymorphisms (fat mass and obesity-associated (FTO), melanocortin-4 receptor (MC4R), leptin (LEP) and leptin receptor (LEPR)) and dietary intake in pregnant women

Genetic variants associated with dietary intake may be important as factors underlying the development of obesity. We investigated the associations between the obesity candidate genes (fat mass and obesity-associated (FTO), melanocortin-4 receptor (MC4R), leptin (LEP) and leptin receptor) and total energy intake and percentage of energy from macronutrients and ultra-processed foods before and during pregnancy. A sample of 149 pregnant women was followed up in a prospective cohort in Rio de Janeiro, Brazil. A FFQ was administered at 5-13 and 30-36 weeks of gestation. Genotyping was performed using real-time PCR. Associations between polymorphisms and the outcomes were investigated through multiple linear regression and ANCOVA having pre-pregnancy dietary intake as a covariate. The A-allele of FTO-rs9939609 was associated with a -6·5 % (95 % CI -12·3, -0·4) decrease in the percentage of energy from protein and positively associated with the percentage of energy from carbohydrates before pregnancy (β=2·6; 95 % CI 0·5, 4·8) and with a 13·3 % (95 % CI 0·7, 27·5) increase in the total energy intake during pregnancy. The C-allele of MC4R-rs17782313 was associated with a -7·6 % (95 % CI -13·8, -1·0) decrease in the percentage of energy from protein, and positively associated with the percentage of energy from ultra-processed foods (β=5·4; 95 % CI 1·1, 9·8) during pregnancy. ANCOVA results revealed changes in dietary intake from pre-pregnancy to pregnancy for FTO-rs9939609 (percentage of energy from ultra-processed foods, P=0·03), MC4R-rs17782313 (total energy intake, P=0·02) and LEP-rs7799039 (total energy intake, P=0·04; percentage of energy from protein, P=0·04). These findings suggest significant associations between FTO-rs9939609, MC4R-rs17782313 and LEP-rs7799039 genes and the components of dietary intake in pregnant women.

Carrying minor allele of FADS1 and haplotype of FADS1 and FADS2 increased the risk of metabolic syndrome and moderate but not low fat diets lowered the risk in two Korean cohorts

PURPOSE

Delta-5-desaturase (fatty acid desaturase-1, FADS1) and delta-6 desaturase (fatty acid desaturase-2, FADS2), rate-limiting enzymes in the biosynthesis of long-chain polyunsaturated fatty acids, may be associated with the risk of metabolic syndrome (MetS). We investigated how FADS1 rs174547 and FADS2 rs2845573 variants modify the prevalence of MetS and whether the risk is modulated by interactions with dietary fat.

METHODS

Genetic, anthropometric, biochemical, and dietary data were collected from the Ansan/Ansung (8842 adults) and City-Rural (5512 adults) cohorts in Korea. The association between FADS1 rs174547(C/T) and FADS2 rs2845573(C/T) variants and MetS was analyzed, as was the interaction of genotypes and fatty acid intake and the risk of MetS after adjusting for MetS-related confounders.

RESULTS

Carriers of FADS1 rs174547 and FADS2 rs2845573 minor alleles had lower serum HDL-cholesterol and glucose levels and higher triglyceride levels than those with major alleles. Ansan/Ansung cohort individuals with FADS1 minor alleles or haplotypes of FADS1 and FADS2 minor alleles had increased risk of MetS, including lower serum HDL-cholesterol and triglyceride levels and blood pressure after adjusting for MetS-related confounders. The City-Rural cohort showed similar results. Total fat intake showed interactions with FADS1 and haplotype variants on MetS risk: MetS frequency was reduced in people consuming moderate fat diets as compared to low fat diets in FADS1 and haplotype of FADS1 and FADS2 major alleles.

CONCLUSION

Korean carriers of the FADS1 rs174547 and FADS2 rs2845573 minor alleles have a greater susceptibility to MetS and moderate fat intake protected against the risk of MetS in carriers of the FADS1 major alleles.

High genetic risk scores for impaired insulin secretory capacity doubles the risk for type 2 diabetes in Asians and is exacerbated by Western-type diets

BACKGROUND

Asians have among the highest incidence of type 2 diabetes (T2DM) in the world, partly due to low β-cell function, causing them to rapidly develop T2DM when insulin resistant. This study tested the hypothesis that genetic polymorphisms are responsible for the low β-cell function and that dietary factors interact with the genes to exacerbate their risk of T2DM.

METHODS

We selected 10 genetic variants of 5 genes involved in insulin secretion (CDKAL1, KCNQ1, IDE, HHEX, and ABCA1) from the genome-wide association studies to calculate the genetic risk scores (GRSs) in 8842 Korean adults in the Ansan/Ansung cohort in the Korean Genome Epidemiology Study. The genetic risk score were divided into low, medium, and high groups, and the association between T2DM and the genetic risk score was measured using logistic regression. We also analysed the interaction between the genetic risk score and the nutrition intakes.

RESULTS

The individual genetic variants were positively associated with T2DM even when adjusted for covariates. Individuals with medium and high genetic risk score had higher T2DM risk by 1.68 and 2.17 folds compared to those with the low genetic risk score after adjusting for covariates. The increased risk was mainly associated with lower HOMA-B, an indicator of insulin secretion capacity, but not HOMA-IR, an indicator of insulin resistance. Subjects with high carbohydrate intakes and a medium genetic risk score did not have a higher risk of T2DM, and the risk was partially mitigated in the high genetic risk score group.

CONCLUSION

Seventy-two percent of the Korean population had either medium or high genetic risk scores for impaired insulin secretion, which approximately doubled their risk of type 2 diabetes, and the risk was exacerbated by consuming a low carbohydrate Western-style diets.

MC4R variant rs17782313 and manifestation of obese phenotype in Pakistani females

MC4R represents a key player involved in melanocortin-mediated control of energy balance. Recently identified near MC4R variant rs17782313 (T > C) can serve as a contributing factor for obese phenotype but its association with obesity has never been sought in a sample of the Pakistani population. The role of genetic variants as causal factors varies across populations. Association studies in a specific population can help us to distinguish global from local gene–gene and gene–environment interactions. This is the first study that investigated the association of rs17782313 with obesity and various obesity-linked anthropometric, metabolic, physical, and behavioural traits in Pakistani subjects including 306 OW/OB (overweight and obese) and 300 NW (normal weight) individuals. The comparison of various aforementioned obesity-linked continuous and categorical variables between OW/OB and NW subjects revealed that almost all variables were found significantly aberrant (p < 0.05) in OW/OB subjects as compared to their age- and gender-matched NW controls indicating greater risk of developing various cardio-metabolic disorders. The genotyping of rs17782313 showed significant association of this variant with obesity and obesity-linked anthropometric traits in females suggesting the gender-specific effect of this variant in our population. The minor allele C increased the risk of obesity by 1.55 times (95% CI = 1.1–2.18, p = 0.01) whereas homozygous CC genotype increased the risk by 2.43 times (95% CI = 1.19–4.96, p = 0.015) in females. However, no association of rs17782313 was observed with any of the obesity-linked metabolic, physical, and behavioural traits except random eating timings. In conclusion, the current study significantly contributes to the knowledge of the genetic proneness to obesity in Pakistani females. This could also be helpful for forthcoming meta-analysis studies elucidating which variants are truly associated with the susceptibility to develop an obese phenotype.

The current study significantly contributes to the knowledge of the genetic proneness to obesity in Pakistani females and could also be helpful for forthcoming meta-analysis studies.

Searching for the relationship between the parameters of metabolic syndrome and the rs17782313 (T>C) polymorphism of the MC4R gene in postmenopausal women

Metabolic syndrome (MS) is widespread in the human population, and its incidence is continuously increasing, generating serious health problems. The purpose of this study was to find the relationship between the parameters of MS and the melanocortin type 4 receptor (MC4R) gene polymorphism in postmenopausal women. The study involved 344 healthy Polish women, who had their last menstrual cycle 1 year ago or earlier. The study included blood analysis, survey, and body measurements. The mean age was 58.5±6.6 years. An increased body mass index was observed in 65.7% and abdominal obesity in 80.3% of the study population. MS was diagnosed in 40.7% of all participants, including 39.3% of women with the T/T genotype and 44.7% of those with the C/X genotype (χ² test; P>0.05). A logistic regression model showed that the probability of MS was higher in patients with the C/X genotype (odds ratio =1.25) (χ² test; P>0.05). The study concluded that MS is a very common condition among postmenopausal women. The C/X genotype of the MC4R gene seems to predispose postmenopausal women to developing some MS symptoms.