Sweet Taste Receptor TAS1R2 Polymorphism (Val191Val) Is Associated with a Higher Carbohydrate Intake and Hypertriglyceridemia among the Population of West Mexico. Nutrients. 2016;8:101. [PMID: 26907331 PMCID: PMC4772063 DOI: 10.3390/nu8020101]

A partial loss-of-function variant (Ile191Val) of the TAS1R2 glucose receptor is associated with enhanced responses to exercise training in older adults with obesity: A translational study

BACKGROUND

The TAS1R2 receptor, known for its role in taste perception, has also emerged as a key regulator of muscle physiology. Previous studies have shown that genetic ablation of TAS1R2 in mice enhances muscle fitness mimicking responses to endurance exercise training. However, the translational relevance of these findings to humans remains uncertain.

METHODS

We explored responses to endurance exercise training in mice and humans with genetic deficiency of TAS1R2. First, we assessed the effects of muscle-specific deletion of TAS1R2 in mice (mKO) or wild type controls (mWT) following 4 weeks of voluntary wheel running (VWR). Next, we investigated the effects of the TAS1R2-Ile191Val (rs35874116) partial loss-of-function variant on responses to a 6-month diet-induced weight loss with exercise training (WLEX), weight loss alone (WL), or education control (CON) interventions in older individuals with obesity. Participants were retrospectively genotyped for the TAS1R2-Ile191Val polymorphism and classified as conventional function (Ile/Ile) or partial loss-of-function (Val carriers: Ile/Val and Val/Val). Body composition, cardiorespiratory fitness, and skeletal muscle mitochondrial function were assessed before and after the intervention.

RESULTS

In response to VWR, mKO mice demonstrated enhanced running endurance and mitochondrial protein content. Similarly, TAS1R2 Val carriers exhibited distinctive improvements in body composition, including increased muscle mass, along with enhanced cardiorespiratory fitness and mitochondrial function in skeletal muscle following the WLEX intervention compared to Ile/Ile counterparts. Notably, every Val carrier demonstrated substantial responses to exercise training and weight loss, surpassing all Ile/Ile participants in overall performance metrics.

CONCLUSIONS

Our findings suggest that TAS1R2 partial loss-of-function confers beneficial effects on muscle function and metabolism in humans in response to exercise training, akin to observations in TAS1R2 muscle-deficient mice. Targeting TAS1R2 may help enhancing exercise training adaptations in individuals with compromised exercise tolerance or metabolic disorders, presenting a potential avenue for personalized exercise interventions.

Personalized medicine and nutrition in hepatology for preventing chronic liver disease in Mexico

Chronic liver disease is a global health issue. Patients with chronic liver disease require a fresh approach that focuses on the genetic and environmental factors that contribute to disease initiation and progression. Emerging knowledge in the fields of Genomic Medicine and Genomic Nutrition demonstrates differences between countries in terms of genetics and lifestyle risk factors such as diet, physical activity, and mental health in chronic liver disease, which serves as the foundation for the implementation of Personalized Medicine and Nutrition (PerMed-Nut) strategies. Most of the world's populations have descended from various ethnic groupings. Mexico's population has a tripartite ancestral background, consisting of Amerindian, European, and African lineages, which is common across Latin America's regional countries. The purpose of this review is to discuss the genetic and environmental components that could be incorporated into a PerMed-Nut model for metabolic-associated liver disease, viral hepatitis B and C, and hepatocellular carcinoma in Mexico. Additionally, the implementation of the PerMed-Nut approach will require updated medicine and nutrition education curricula. Training and equipping future health professionals and researchers with new clinical and investigative abilities focused on preventing liver illnesses in the field of genomic hepatology globally is a vision that clinicians and nutritionists should be concerned about.

Understanding the determinants of sweet taste liking in the African and East Asian ancestry groups in the U.S.-A study protocol

BACKGROUND

The liking for sweet taste is a powerful driver for consuming added sugars, and therefore, understanding how sweet liking is formed is a critical step in devising strategies to lower added sugars consumption. However, current research on the influence of genetic and environmental factors on sweet liking is mostly based on research conducted with individuals of European ancestry. Whether these results can be generalized to people of other ancestry groups warrants investigation.

METHODS

We will determine the differences in allele frequencies in sweet-related genetic variants and their effects on sweet liking in 426 adults of either African or East Asian ancestry, who have the highest and lowest average added sugars intake, respectively, among ancestry groups in the U.S. We will collect information on participants' sweet-liking phenotype, added sugars intake (sweetness exposure), anthropometric measures, place-of-birth, and for immigrants, duration of time living in the U.S. and age when immigrated. Ancestry-specific polygenic scores of sweet liking will be computed based on the effect sizes of the sweet-related genetic variants on the sweet-liking phenotype for each ancestry group. The predictive validity of the polygenic scores will be tested using individuals of African and East Asian ancestry from the UK Biobank. We will also compare sweet liking between U.S.-born individuals and immigrants within each ancestry group to test whether differences in environmental sweetness exposure during childhood affect sweet liking in adulthood.

DISCUSSION

Expanding genetic research on taste to individuals from ancestry groups traditionally underrepresented in such research is consistent with equity goals in sensory and nutrition science. Findings from this study will help in the development of a more personalized nutrition approach for diverse populations.

TRIAL REGISTRATION

This protocol has been preregistered with the Center for Open Science (https://doi.org/10.17605/OSF.IO/WPR9E).

Low Dietary Betaine Intake Is Associated with Increased Blood Cholesterol in Mexican Subjects

BACKGROUND

Betaine, an osmolyte derivative of the metabolite choline and the amino acid glycine, acts as a methyl donor in the conversion of homocysteine to methionine and is involved in the maintenance of adequate lipid metabolism. There is growing evidence for the role of betaine in the development of various lipid-related diseases, including dyslipidemia and cardiovascular risk. This study aimed to analyze associations between betaine intake and blood lipid profiles in Mexican subjects.

METHODS

A total of 212 adults were randomly recruited in the city of Tijuana, Baja California, Mexico. Betaine intake was estimated using Nutritionist Pro software. Body composition and metabolic measurements were obtained by conventional methods. In the total sample, the average intake of betaine was 14.32 mg/d. Individuals were categorized into three groups according to tertiles of betaine consumption: tertile/group 1 (<4.16 mg/d), tertile/group 2 (4.16-12.02 mg/d), and tertile/group 3 (>12.02 mg/d).

RESULTS

Compared to group 3, subjects within group 1 had higher serum levels of total cholesterol (p = 0.001), LDL-c (p = 0.026), and non-HDL-c (p = 0.021). In addition, significant negative Pearson correlations were found between betaine intake and the serum levels of total cholesterol (r = -0.432, 95% CI, -0.684, -0.185, p = 0.001), LDL-c (r = -0.370, 95% CI, -0.606, -0.134, p = 0.002), and non-HDL-c (r = -0.351, 95%CI, -0.604, -0.098, p = 0.007).

CONCLUSIONS

Our results show that a low intake of betaine is associated with elevated blood cholesterol levels in Mexican subjects. On this basis, betaine consumption could be used as an additional dietary measure for cardiovascular care. However, additional studies are required to confirm our results in other Mexican regions as well as in other populations worldwide.

White adipose tissue: Distribution, molecular insights of impaired expandability, and its implication in fatty liver disease

We are far behind the 2025 World Health Organization (WHO) goal of a zero increase in obesity. Close to 360 million people in Latin America and the Caribbean are overweight, with the highest rates observed in the Bahamas, Mexico, and Chile. To achieve relevant progress against the obesity epidemic, scientific research is essential to establish uniform practices in the study of obesity pathophysiology (using pre-clinical and clinical models) that ensure accuracy, reproducibility, and transcendent outcomes. The present review focuses on relevant aspects of white adipose tissue (WAT) expansion, underlying mechanisms of inefficient expandability, and its repercussion in ectopic lipid accumulation in the liver during nutritional abundance. In addition, we highlight the potential role of disrupted circadian rhythm in WAT metabolism. Since genetic factors also play a key role in determining an individual's predisposition to weight gain, we describe the most relevant genes associated with obesity in the Mexican population, underlining that most of them are related to appetite control.

Understanding the Determinants of Sweet Liking in the African and East Asian Ancestry Groups in the U.S. - A Study Protocol

Background

The liking for sweet taste is a powerful driver for consuming added sugars, and therefore, understanding how sweet liking is formed is a critical step in devising strategies to lower added sugars consumption. However, current research on the influence of genetic and environmental factors on sweet liking is mostly based on research conducted with individuals of European ancestry. Whether these results can be generalized to people of other ancestry groups warrants investigation.

Methods

We will determine the differences in allele frequencies in sweet-related genetic variants and their effects on sweet liking in 426 adults of either African or East Asian ancestry, who have the highest and lowest average added sugars intake, respectively, among ancestry groups in the U.S. We will collect information on participants' sweet-liking phenotype, added sugars intake (sweetness exposure), anthropometric measures, place-of-birth, and for immigrants, duration of time living in the U.S. and age when immigrated. Ancestry-specific polygenic scores of sweet liking will be computed based on the effect sizes of the sweet-related genetic variants on the sweet-liking phenotype for each ancestry group. The predictive validity of the polygenic scores will be tested using individuals of African and East Asian ancestry from the UK Biobank. We will also compare sweet liking between U.S.-born individuals and immigrants within each ancestry group to test whether differences in environmental sweetness exposure during childhood affect sweet liking in adulthood.

Discussion

Expanding genetic research on taste to individuals from ancestry groups traditionally underrepresented in such research is consistent with equity goals in sensory and nutrition science. Findings from this study will help in the development of a more personalized nutrition approach for diverse populations.

Trial registration

This protocol has been preregistered with the Center for Open Science (https://doi.org/10.17605/OSF.IO/WPR9E) and is approved by the City University of New York Human Research Protection Program (IRB#: 2023-0064-Brooklyn).

Dietary Intake of Capsaicin and Its Association with Markers of Body Adiposity and Fatty Liver in a Mexican Adult Population of Tijuana

Background: Capsaicin (CAP) is the main chemical component responsible for the pungency (burning pain) of the chili plant (capsicum spp.), whose metabolic functions include energy balance and fatty acid oxidation. The aim of this study is to analyze the association of dietary capsaicin consumption with markers of adiposity and fatty liver in a Mexican adult population. Methods: This cross-sectional/analytical study recruited 221 subjects aged 18 to 65 years who were resident in the city of Tijuana, Baja California, Mexico. The daily CAP intake was analyzed through a validated chili/CAP consumption questionnaire. Anthropometric and biochemical measurements were performed following standardized protocols. Adjusted Pearson's correlations were applied to analyze the association of CAP with adiposity and fatty liver markers. Results: In this study, the daily average consumption of CAP was 152.44 mg. The dietary CAP consumption positively correlated with BMI (r = 0.179, p = 0.003), hip circumference (r = 0.176, p = 0.004) and body adiposity index (r = 0.181, p = 0.001. Likewise, the daily CAP intake positively correlated with hepatic steatosis index (r = 0.158, p = 0.004), fatty liver index (r = 0.141, p = 0.003) and lactate dehydrogenase (r = 0.194, p = 0.016) after statistical settings. Conclusions: The results of this study suggest positive associations between dietary CAP consumption and the markers of body adiposity and fatty liver in a Mexican adult population.

Interkingdom Detection of Bacterial Quorum-Sensing Molecules by Mammalian Taste Receptors

Bitter and sweet taste G protein-coupled receptors (known as T2Rs and T1Rs, respectively) were originally identified in type II taste cells on the tongue, where they signal perception of bitter and sweet tastes, respectively. Over the past ~15 years, taste receptors have been identified in cells all over the body, demonstrating a more general chemosensory role beyond taste. Bitter and sweet taste receptors regulate gut epithelial function, pancreatic β cell secretion, thyroid hormone secretion, adipocyte function, and many other processes. Emerging data from a variety of tissues suggest that taste receptors are also used by mammalian cells to "eavesdrop" on bacterial communications. These receptors are activated by several quorum-sensing molecules, including acyl-homoserine lactones and quinolones from Gram-negative bacteria such as Pseudomonas aeruginosa, competence stimulating peptides from Streptococcus mutans, and D-amino acids from Staphylococcus aureus. Taste receptors are an arm of immune surveillance similar to Toll-like receptors and other pattern recognition receptors. Because they are activated by quorum-sensing molecules, taste receptors report information about microbial population density based on the chemical composition of the extracellular environment. This review summarizes current knowledge of bacterial activation of taste receptors and identifies important questions remaining in this field.

Interactions between Bitter Taste Receptor Gene Variants and Dietary Intake Are Associated with the Incidence of Type 2 Diabetes Mellitus in Middle-Aged and Older Korean Adults

The relationship between the variants of bitter taste receptor gene TAS2R4, dietary intake, and incidence of type 2 diabetes mellitus (T2DM) remains unclear. Hence, we aimed to examine the association of TAS2R4 rs2233998 variants with T2DM incidence in middle-aged and older Korean adults to understand if their association was modulated by dietary intake. Data of the Ansan-Ansung cohort from the Korean Genome and Epidemiology Study were used in this study. A total of 4552 Korean adults aged 40-69 years with no history of T2DM or cancer at baseline were followed-up for 16 years. Dietary intake was assessed using a 103-item food frequency questionnaire, and new T2DM cases were defined based on the World Health Organization and International Diabetes Federation criteria. Multivariate Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for T2DM incidence. During the mean follow-up period of 11.97 years, 1082 (23.77%) new T2DM cases were identified. Women carrying the TT genotype of TAS2R4 rs2233998 exhibited 1.48 times higher incidence of T2DM (HR: 1.48; 95 CI: 1.13-1.93) than those carrying the CC genotype. TAS2R4 rs2233998 variants were positively associated with the incidence of T2DM among Korean women with high intakes of carbohydrates or sugars and low intakes of fruits or vegetables. TT carrier women in the highest tertile of carbohydrate or sugar intake exhibited an increased incidence of T2DM (HR: 2.08, 95% CI: 1.33-3.27 for carbohydrates; HR: 2.31, 95% CI: 1.53-3.51 for sugars) than CC carrier women. Women carrying the TT genotype in the lowest tertile exhibited an increased incidence of T2DM (HR: 1.55, 95% CI: 1.02-2.37 for vegetables; HR: 1.62, 95% CI: 1.06-2.48 for fruits) than women carrying the CC genotype in the highest tertile of vegetable or fruit consumption. However, no association was observed between TAS2R4 rs2233998 variants and dietary intake with T2DM incidence in Korean men. Our findings suggest that variants of TAS2R4 rs2233998 are associated with T2DM incidence, and their associations are strengthened by excessive intake of carbohydrates or sugars and inadequate intake of fruits or vegetables. Diet encompassing optimal intake of carbohydrates or sugars and high intake of fruits or vegetables may minimize the risk of developing T2DM.

Genetic variation in sweet taste receptors and a mechanistic perspective on sweet and fat taste sensation in the context of obesity

Taste sensation enables humans to make nutritionally important decisions such as food preference and consumption. It functions as deterministic factors for unpropitious eating behavior, leading to overweight and obesity. The hedonistic feeling on consumption of fat and sugar-rich meals, in particular, has a negative influence on health. In addition, impairment in the taste receptors alters the downstream signaling of taste transduction pathway. Hence, genetic polymorphism in typical taste receptors is a predictor of taste sensitivity variance across individuals. The present review summarizes the effect of a single nucleotide polymorphism (SNP) in sweet taste receptors (T1R2/T1R3) on taste perception among individuals of various body mass index (BMI). Furthermore, in the context of obesity, we discussed the possibility of crosstalk between fat and sweet receptors as well as taste dysfunction in diseased individuals. In overall, a greater understanding of the physiological relationship between taste receptors, altered taste sensitivity, and genetic polymorphisms should lead to more effective obesity prevention approaches.

Associations between Sweet Taste Sensitivity and Polymorphisms (SNPs) in the TAS1R2 and TAS1R3 Genes, Gender, PROP Taster Status, and Density of Fungiform Papillae in a Genetically Homogeneous Sardinian Cohort

Individual differences in sweet taste sensitivity can affect dietary preferences as well as nutritional status. Despite the lack of consensus, it is believed that sweet taste is impacted by genetic and environmental variables. Here we determined the effect of well-established factors influencing the general taste variability, such as gender and fungiform papillae density, specific genetic variants (SNPs of TAS1R2 and TAS1R3 receptors genes), and non-specific genetic factors (PROP phenotype and genotype), on the threshold and suprathreshold sweet taste sensitivity. Suprathreshold measurements showed that the sweet taste response increased in a dose-dependent manner, and this was related to PROP phenotype, gender, rs35874116 SNP in the TAS1R2 gene, and rs307355 SNP in the TAS1R3 gene. The threshold values and density of fungiform papillae exhibited a strong correlation, and both varied according to PROP phenotype. Our data confirm the role of PROP taste status in the sweet perception related to fungiform papilla density, show a higher sweet sensitivity in females who had lower BMI than males, and demonstrate for the first time the involvement of the rs35874116 SNP of TAS1R2 in the sweet taste sensitivity of normal weight subjects with body mass index (BMI) ranging from 20.2 to 24.8 kg/m2. These results may have an important impact on nutrition and health mostly in subjects with low taste ability for sweets and thus with high vulnerability to developing obesity or metabolic disease.

Whole-Exome Sequencing identified Olfactory Receptor genes as a key contributor to extreme obesity with progression to nonalcoholic steatohepatitis in Mexican patients: Olfactory receptor genes in obese NASH patients

INTRODUCTION AND OBJECTIVES

Obesity is a global health problem that triggers fat liver accumulation. The prevalence of obesity and the risk of non-alcoholic steatohepatitis (NASH) among young obese Mexican is high. Furthermore, genetic predisposition is a key factor in weight gain and disrupts metabolism. Herein, we used Whole-Exome Sequencing to identify potential causal variants and the biological processes that lead to obesity with progression to NASH among Mexican patients.

MATERIALS AND METHODS

Whole-Exome Sequencing was performed in nine obese patients with NASH diagnosis with a BMI ≥30 kg/m² and one control (BMI=24.2 kg/m²) by using the Ion S5^TM platform. Genetic variants were determined by Ion Reporter software. Enriched GO biological set genes were identified by the WebGestalt tool. Genetic variants within ≥2 obese NASH patients and having scores of SIFT 0.0-0.05 and Polyphen 0.85-1.0 were categorized as pathogenic.

RESULTS

A total of 1359 variants with a probable pathogenic effect were determined in obese patients with NASH diagnosis. After several filtering steps, the most frequent pathogenic variants found were rs25640-HSD17B4, rs8105737-OR1I1, rs998544-OR5R1, and rs4916685, rs10037067, and rs2366926 in ADGRV1. Notably, the primary biological processes affected by these pathogenic variants were the sensory perception and detection of chemical stimulus pathways in which the olfactory receptor gene family was the most enriched.

CONCLUSIONS

Variants in the olfactory receptor genes were highly enriched in Mexican obese patients that progress to NASH and could be potential targets of association studies.

The rs35874116 single nucleotide polymorphism increases sweet intake and the risk of severe early childhood caries: a case–control study

Background

Dental caries is one of the most prevalent chronic diseases worldwide among children. The rs35874116 single nucleotide polymorphism (SNP) in the sweet receptor gene TAS1R2 has been associated with dental caries at a high risk in permanent teeth among school children and adults. To date, little is known about the association of this SNP with sweet intake and caries risk in the primary school children.

Methods

Total of 236 children were included, namely 118 subjects in the non-caries (NC) group and severe early childhood caries (S-ECC) group, respectively. Oral mucosa cells were collected from all the selected children, and the full length of exon 3 in TAS1R2 was sequenced to analyse rs35874116 polymorphism. A questionnaire was used to collect information about socio-demographic information, frequency of sweet intake and oral hygiene habits. Multiple logistic regression models were applied to assess the relationship of rs35874116 polymorphism with frequency of sweet intake and S-ECC among the five-year-old children.

Results

Children with the TT genotype of rs35874116 had a higher frequency of sweet intake than CT/CC carriers (51.3% vs. 32.7%; x2 = 5.436, p = 0.020), and S-ECC individuals were more likely to be TT genotype carriers than NC individuals (53.5% vs. 46.5%; x2 = 4.353, p = 0.037). Multiple logistic regression analyses showed that the TT genotype of rs35874116 was not only significantly related to the frequency of sweet intake (OR = 2.25, 95% CI = 1.14–4.44) but also significantly associated with S-ECC (OR = 2.11, 95% CI = 1.01 ~ 4.42).

Conclusions

The rs35874116 polymorphism might increase sweet intake and the risk of S-ECC among five-year-old children in Nanning, China.

Polymorphisms, diet and nutrigenomics

Every human being possesses an exclusive nutritional blueprint inside their genes. Bioactive food components and nutrients affect the expression of such genes. Nutrigenomics is the science that analyzes gene-nutrient interactions (nutrigenetics), which can lead to the development of personalized nutritional recommendations to maintain optimal health and prevent disease. Genomic diversity among various ethnic groups might affect nutrients bioavailability as well as their metabolism. Nutrigenomics combines different branches of science including nutrition, bioinformatics, genomics, molecular biology, molecular medicine, and epidemiology. Genes regulate intake and metabolism of different nutrients, while nutrients positively or negatively influence the expression of a number of genes; testing of specific genetic polymorphisms may therefore become a useful tool to manage weight loss and to fully understand gene-nutrient interactions. Indeed, several approaches are used to study gene-nutrient interactions: epigenetics, the study of genome modification not related to changes in nucleotide sequence; transcriptomics, the study of tissue-specific and time-specific RNA transcripts; proteomics, the study of proteins involved in biological processes; and metabolomics, the study of changes of primary and secondary metabolites in body fluids and tissues. Hence, the use of nutrigenomics to improve and optimize a healthy, balanced diet in clinical settings could be an effective approach for long-term lifestyle changes that might lead to consistent weight loss and improve quality of life.

The Ile191Val Variant of the TAS1R2 Subunit of Sweet Taste Receptors Is Associated With Reduced HbA1c in a Human Cohort With Variable Levels of Glucose Homeostasis

The Ile191Val variant of the TAS1R2 gene of sweet taste receptors causes a partial loss-of-function and is associated with reduced glucose excursions in a healthy lean cohort. However, it is unclear whether this polymorphism contributes to the regulation of glucose homeostasis in metabolically unhealthy individuals. Thus, we used participants with variable glycemic profiles and obesity to assess the effects of the TAS1R2-Ile191Val variant. We found that the Val minor allele carriers had lower HbA1c at all levels of fasting glucose and glucose tolerance. These effects were not due to differences in beta-cell function or insulin sensitivity assessed with a frequently sampled intravenous glucose tolerance test. This study extends our previous findings and provides further evidence that sweet taste receptor function may contribute to glucose regulation in humans.

Oral Microbiota-Host Interaction Mediated by Taste Receptors

Taste receptors, originally identified in taste buds, function as the periphery receptors for taste stimuli and play an important role in food choice. Cohort studies have revealed that single nucleotide polymorphisms of taste receptors such as T1R1, T1R2, T2R38 are associated with susceptibility to oral diseases like dental caries. Recent studies have demonstrated the wide expression of taste receptors in various tissues, including intestinal epithelia, respiratory tract, and gingiva, with an emerging role of participating in the interaction between mucosa surface and microorganisms via monitoring a wide range of metabolites. On the one hand, individuals with different oral microbiomes exhibited varied taste sensitivity, suggesting a potential impact of the oral microbiota composition on taste receptor function. On the other hand, animal studies and in vitro studies have uncovered that a variety of oral cells expressing taste receptors such as gingival solitary chemosensory cells, gingival epithelial cells (GECs), and gingival fibroblasts can detect bacterial signals through bitter taste receptors to trigger host innate immune responses, thus regulating oral microbial homeostasis. This review focuses on how taste receptors, particularly bitter and sweet taste receptors, mediate the oral microbiota-host interaction as well as impact the occurrence and development of oral diseases. Further studies delineating the role of taste receptors in mediating oral microbiota-host interaction will advance our knowledge in oral ecological homeostasis establishment, providing a novel paradigm and treatment target for the better management of dental infectious diseases.

Are taste variations associated with the liking of sweetened and unsweetened coffee?

OBJECTIVE

In this study, we evaluated the influence of taste phenotypes and genotypes on the hedonics of sweetened and unsweetened coffee.

METHODS

Liking of espresso coffee from food questionnaire and of a ready-to-drink unsweetened coffee beverage was measured using a 9-point hedonic scale in 1551 Italian individuals. Perception and liking for different bitter and sweet compounds were also collected. Genotyping of selected Single Nucleotide Polymorphisms (SNPs) in five taste genes (TAS1R3, GNAT3, TAS2R14, TAS2R19, TAS2R38) was performed. Linear and logistic regression models, including sex and gender as covariates, were used to test the relationship of taste phenotypes and selected SNPs with coffee liking.

RESULTS

We found that increased caffeine bitterness perception was associated with an increasing liking for sweetened coffee (p-value = 0.018) and decreased liking of unsweetened coffee (p-value = 0.034). The liking of unsweetened coffee beverage was also negatively associated with sweet intensity perception (p-value = 0.03). Analysis of SNPs in taste-related genes showed that rs6467192 G allele (intron 4 variant) in GNAT3 sweet taste gene was associated with higher liking of sweetened coffee (p-value = 0.002) and lower liking of unsweetened coffee (p-value = 0.01). An association also emerged between unsweetened coffee and SNPs in bitter receptor genes, with rs2597979 in TAS2R14 gene associated with liking of unsweetened coffee (p-value = 0.004) and rs10772420 in TAS2R19 gene associated with liking of both unsweetened espresso coffee and coffee beverage (p-value = 0.04 and p-value = 0.03, respectively).

CONCLUSION

These findings suggested that individual preference for sweetened and unsweetened coffee may be influenced by both phenotypic and nucleotide variations in bitter and sweet taste sensitivity.

Genetic polymorphisms are not associated with energy intake one year after Roux-Y gastric bypass (RYGB) in women

BACKGROUND

This study aimed to investigate the influence of food intake on body weight loss and the association of gene polymorphisms, 1 year after Roux-en-Y gastric bypass (RYGB) surgery.

METHODS

In total, ninety-five obese women (age ranged 20-50 years) in a Brazilian cohort underwent RYGB surgery and completed the study. Anthropometric measurements and food intake were assessed before and 1 year after surgery. Twelve gene polymorphisms (GHRL rs26802; GHSR rs572169; LEP rs7799039; LEPR rs1137101; 5-HT2C rs3813929; UCP2 rs659366; UCP2 rs660339; UCP3 rs1800849; SH2B1 rs7498665; TAS1R2 rs35874116; TAS1R2 rs9701796; and FTO rs9939609) were determined using a real-time PCR reaction and a TaqMan assay. The subjects were divided into quartiles regarding to percentage of excess weight loss (%EWL). The effect of genetic variants on energy and macronutrient intake was evaluated by simple logistic regression, followed by multiple logistic regression.

RESULTS

It was found that subjects in the first and second quartile showed a higher initial body mass index (BMI). Energy and macronutrient intake before and 1 year after RYGB surgery did not differ between the %EWL quartiles. None of gene polymorphisms investigated showed an association with the estimated energy intake 1 year after surgery.

CONCLUSION

In conclusion, the estimate energy and food intake did not predict a greater body weight loss 1 year after RYGB surgery. In addition, the 12 gene polymorphism investigated did not affect the energy intake among female patients. This article is protected by copyright. All rights reserved.

Taste Receptors: The Gatekeepers of the Airway Epithelium

Taste receptors are well known for their role in the sensation of taste. Surprisingly, the expression and involvement of taste receptors in chemosensory processes outside the tongue have been recently identified in many organs including the airways. Currently, a clear understanding of the airway-specific function of these receptors and the endogenous activating/inhibitory ligands is lagging. The focus of this review is on recent physiological and clinical data describing the taste receptors in the airways and their activation by secreted bacterial compounds. Taste receptors in the airways are potentially involved in three different immune pathways (i.e., the production of nitric oxide and antimicrobial peptides secretion, modulation of ciliary beat frequency, and bronchial smooth muscle cell relaxation). Moreover, genetic polymorphisms in these receptors may alter the patients’ susceptibility to certain types of respiratory infections as well as to differential outcomes in patients with chronic inflammatory airway diseases such as chronic rhinosinusitis and asthma. A better understanding of the function of taste receptors in the airways may lead to the development of a novel class of therapeutic molecules that can stimulate airway mucosal immune responses and could treat patients with chronic airway diseases.

The Ile191Val is a partial loss-of-function variant of the TAS1R2 sweet-taste receptor and is associated with reduced glucose excursions in humans

OBJECTIVE

Sweet taste receptors (STR) are expressed in the gut and other extra-oral tissues, suggesting that STR-mediated nutrient sensing may contribute to human physiology beyond taste. A common variant (Ile191Val) in the TAS1R2 gene of STR is associated with nutritional and metabolic outcomes independent of changes in taste perception. It is unclear whether this polymorphism directly alters STR function and how it may contribute to metabolic regulation.

METHODS

We implemented a combination of in vitro biochemical approaches to decipher the effects of TAS1R2 polymorphism on STR function. Then, as proof-of-concept, we assessed its effects on glucose homeostasis in apparently healthy lean participants.

RESULTS

The Ile191Val variant causes a partial loss of function of TAS1R2 through reduced receptor availability in the plasma membrane. Val minor allele carriers have reduced glucose excursions during an OGTT, mirroring effects previously seen in mice with genetic loss of function of TAS1R2. These effects were not due to differences in beta-cell function or insulin sensitivity.

CONCLUSIONS

Our pilot studies on a common TAS1R2 polymorphism suggest that STR sensory function in peripheral tissues, such as the intestine, may contribute to the regulation of metabolic control in humans.

Adult rats from undernourished dams show sex-dependent impaired expression in taste papillae and hypothalamus of genes responsible for sweet and fat detection and signalling

AIM

Individuals undernourished in utero or during early life are at high risk of developing obesity and metabolic disorders and show an increased preference for consuming sugary and fatty food. This study aimed at determining whether impaired taste detection and signalling in the lingual epithelium and the brain might contribute to this altered pattern of food intake.

METHODS

The preference for feeding fat and sweet food and the expression in circumvallate papillae and hypothalamus of genes coding for sweet and fat receptors and transducing pathways were evaluated in adult rats born to control or calorie-restricted dams. Expression in the hypothalamus and the brain's reward system of genes involved in the homeostatic and hedonic control of food intake was also determined.

RESULTS

Male and female undernourished animals exhibited increased expression in taste papillae and hypothalamus of T1R1, T1R2, CD36, gustducin, TRMP5 and PLC-β2 genes, all of which modulate sweet and fat detection and intracellular signalling. However, the severity of the effect was greater in females than in males. Moreover, male, but not female, undernourished rats consumed more standard and sweetened food than their control counterparts and presented increased hypothalamic AgRP and NPY mRNAs levels together with enhanced dopamine transporter and dopamine receptor D2 expression in the ventral tegmental area.

CONCLUSIONS

Maternal undernutrition induces sex-specific changes in food preferences and gene expression in taste papillae, hypothalamus and brain reward regions. The gene expression alterations in the male offspring are in line with their preference for consuming sugary and fatty food.

The complex relationship between metabolic syndrome and sweeteners

Metabolic syndrome is a multifactorial disorder originating from central obesity through a high caloric intake and a sedentary lifestyle. Metabolic syndrome increases the risk of type 2 diabetes (T2D) disease, converting it to one of the costliest chronic diseases, which reduces life quality. A strategy proposed by the food industry to reduce this problem is the generation of low-caloric products using sweeteners, which are compounds that can substitute sucrose, given their sweet taste. For many years, it was assumed that sweeteners did not have a relevant interaction in metabolism. However, recent studies have demonstrated that sweeteners interact either with metabolism or with gut microbiota, in which sweet-taste receptors play an essential role. This review presents an overview of the industrial application of most commonly consumed sweeteners. In addition, the interaction of sweeteners within the body, including their absorption, distribution, metabolism, gut microbiota metabolism, and excretion is also reviewed. Furthermore, the complex relationship between metabolic syndrome and sweeteners is also discussed, presenting results from in vivo and clinical trials. Findings from this review indicate that, in order to formulate sugar-free or noncaloric food products for the metabolic syndrome market, several factors need to be considered, including the dose, proportions, human metabolism, and interaction of sweeteners with gut microbiota and sweet-taste receptors. More clinical studies, including the metabolic syndrome, are needed to better understand the interaction of sweeteners with the human body, as well as their possible effect on the generation of dysbiosis.

Polymorphic variants in Sweet and Umami taste receptor genes and birthweight

The first thousand days of life from conception have a significant impact on the health status with short, and long-term effects. Among several anthropometric and maternal lifestyle parameters birth weight plays a crucial role on the growth and neurological development of infants. Recent genome wide association studies (GWAS) have demonstrated a robust foetal and maternal genetic background of birth weight, however only a small proportion of the genetic hereditability has been already identified. Considering the extensive number of phenotypes on which they are involved, we focused on identifying the possible effect of genetic variants belonging to taste receptor genes and birthweight. In the human genome there are two taste receptors family the bitter receptors (TAS2Rs) and the sweet and umami receptors (TAS1Rs). In particular sweet perception is due to a heterodimeric receptor encoded by the TAS1R2 and the TAS1R3 gene, while the umami taste receptor is encoded by the TAS1R1 and the TAS1R3 genes. We observed that carriers of the T allele of the TAS1R1-rs4908932 SNPs showed an increase in birthweight compared to GG homozygotes Coeff: 87.40 (35.13-139.68) p-value = 0.001. The association remained significant after correction for multiple testing. TAS1R1-rs4908932 is a potentially functional SNP and is in linkage disequilibrium with another polymorphism that has been associated with BMI in adults showing the importance of this variant from the early stages of conception through all the adult life.

Single nucleotide polymorphisms in sweet, fat, umami, salt, bitter and sour taste receptor genes are associated with gustatory function and taste preferences in young adults

Taste is a fundamental mechanism whereby compounds are detected orally, yet it is highly variable among individuals. The variability in taste that is attributable to genetics is not well-characterized despite its potential role in food selection, and therefore, eating habits that contribute to risk of overweight and obesity. In order to implicate measures of taste function and preference as potentially deterministic factors in adverse eating behaviors that lead to obesity, it must be shown that a relationship exists between genetic variation in taste receptor genes and psychophysical measures of taste in the absence high body mass index. The primary objective of this pilot study was to investigate the relationship between single nucleotide polymorphisms (SNPs) in taste receptor genes and 3 different psychophysical measures of taste in healthy young adults. Sweet, salt, umami, fat, sour, and bitter taste receptor gene SNPs were genotyped in 49 participants (ages 24.6 ± 0.6 years) who completed testing to determine oral detection threshold (DT), suprathreshold sensitivity (ST) and taste preference (PR). A simultaneous association test was conducted between each SNP and the 3 taste outcomes (DT, ST, and PR). Twelve SNPs were associated with at least one of the 3 taste outcomes. Associations were observed between SNPs in taste receptor genes and psychophysical measures of sweet, fat, umami, and salt taste. These results suggest that differences in interindividual psychophysical measures of tastes, namely DT, ST, and PR, may be partially attributed to genetic variation in taste receptor genes. Future studies are warranted to investigate if these findings have consequences for habitual dietary intake of foods that elicit these tastes.

Ecological Sensing Through Taste and Chemosensation Mediates Inflammation: A Biological Anthropological Approach

Ecological sensing and inflammation have evolved to ensure optima between organism survival and reproductive success in different and changing environments. At the molecular level, ecological sensing consists of many types of receptors located in different tissues that orchestrate integrated responses (immune, neuroendocrine systems) to external and internal stimuli. This review describes emerging data on taste and chemosensory receptors, proposing them as broad ecological sensors and providing evidence that taste perception is shaped not only according to sense epitopes from nutrients but also in response to highly diverse external and internal stimuli. We apply a biological anthropological approach to examine how ecological sensing has been shaped by these stimuli through human evolution for complex interkingdom communication between a host and pathological and symbiotic bacteria, focusing on population-specific genetic diversity. We then focus on how these sensory receptors play a major role in inflammatory processes that form the basis of many modern common metabolic diseases such as obesity, type 2 diabetes, and aging. The impacts of human niche construction and cultural evolution in shaping environments are described with emphasis on consequent biological responsiveness.

Genetic Differences in Taste Receptors: Implications for the Food Industry

Inborn genetic differences in chemosensory receptors can lead to differences in perception and preference for foods and beverages. These differences can drive market segmentation for food products as well as contribute to nutritional status. This knowledge may be essential in the development of foods and beverages because the sensory profiles may not be experienced in the same way across individuals. Rather, distinct consumer groups may exist with different underlying genetic variations. Identifying genetic factors associated with individual variability can help better meet consumer needs through an enhanced understanding of perception and preferences. This review provides an overview of taste and chemesthetic sensations and their receptors, highlighting recent advances linking genetic variations in chemosensory genes to perception, food preference and intake, and health. With growing interest in personalized foods, this information is useful for both food product developers and nutrition health professionals alike.

Association of Apolipoprotein e2 Allele with Insulin Resistance and Risk of Type 2 Diabetes Mellitus Among an Admixed Population of Mexico

PURPOSE

This study aimed to analyze the association of the apolipoprotein E (ApoE) polymorphisms with type 2 diabetes mellitus (T2DM) among the admixed population of West Mexico.

PATIENTS AND METHODS

ApoE genotypes were determined in 168 T2DM patients and 449 non-diabetic control subjects from the general admixed population of West Mexico. The non-diabetic subjects were stratified according to body mass index (BMI) in normal weight (n=186), overweight (n=138), and obesity (n=125). ApoE genotypes were assessed by using a TaqMan allelic discrimination assay, insulin resistance (IR) by HOMA-IR, and biochemistry with a dry chemistry assay.

RESULTS

The rate of dyslipidemias and IR increased by BMI category among the control subjects. The greater shift in the prevalence of dyslipidemia was observed from normal weight (51.4%) to overweight (76.6%), p<0.01. Normal weight or obese e4 allele carriers had a higher level of total cholesterol and hypercholesterolemia than non-e4 carriers. Among the T2DM patients, the e2 carriers had abnormal HOMA-IR value than the non-e2 carriers (p=0.002). Comparatively, between the T2DM patients vs non-diabetics, the e2e3 genotype or e2 allele conferred a higher risk for T2DM (adjusted OR= 2.36, 95% CI 1.28-4.34, p=0.006 and adjusted OR=2.1, 95% Cl 1.20-3.79, p=0.009, respectively).

CONCLUSION

The ApoE e2 allele was associated with IR and the risk of T2DM in subjects from the general admixed population of West Mexico.

Genetic variants in taste-related genes and risk of pancreatic cancer

Pancreatic ductal adenocarcinoma is an aggressive and relatively rare cancer with a dismal 5-year survival rate and a clear genetic background. Genetic variants in taste receptors and taste-related genes have been associated with a variety of human traits and phenotypes among which several cancer types and pancreatic cancer risk factors. In this study, we analysed 2854 single-nucleotide polymorphisms in 50 taste-related genes, including 37 taste receptors. To cover all the genetic variability of the selected genes and to include also regulatory elements, we added 5000 nucleotides to both ends of each gene. We used a two-phase approach, with the PanScan data set (3314 cases and 3431 controls) as the discovery phase and PanC4 (3893 cases and 3632 controls) as validation phase, for a total of 7207 cases and 7063 controls. The datasets were downloaded from the NCBI database of genotypes and phenotypes (dbGaP). We observed that the taste 1 receptor member 2 (TAS1R2)-rs11261087 variant was associated with pancreatic cancer risk in both phases independently, with a consistent association of the T allele with decreased risk of developing the disease [phase 1 odds ratio (OR) = 0.89, 95% confidence interval (CI) 0.80-0.98; phase 2 OR = 0.91, 95% CI 0.83-0.99; all subjects together OR = 0.90, 95% CI 0.84-0.96, P = 0.002]. However, neither the association observed in the validation phase nor those observed in the joint analysis were statistically significant considering multiple testing. Functional studies are warranted to better understand the impact of the genetic variability of TAS1R2 on PDAC risk.

Interactions between DRD2/ANKK1 TaqIA Polymorphism and Dietary Factors Influence Plasma Triglyceride Concentrations in Diabetic Patients from Western Mexico: A Cross-sectional Study

This study aimed to screen relevant interactions between DRD2/ANKK1 TaqIA polymorphism and dietary intakes with reference to phenotypical features in patients with T2D from western Mexico. In this cross-sectional study, a total of 175 T2D patients were enrolled. Dietary intake was evaluated using 3-day food records and appropriate software. Glycemic and blood lipid profiles were measured by standardized methods. Genotyping of the DRD2/ANKK1 TaqIA polymorphism was performed by the RFLP method. Gene-diet interactions regarding anthropometric and metabolic phenotypes were screened by adjusted multiple linear regression analyses. Genotype frequencies of the DRD2/ANKK1 TaqIA polymorphism were A1A1 (16.0%), A1A2 (52.6%), and A2A2 (31.4%). Statistically significant interactions between the DRD2/ANKK1 TaqIA genotypes and dietary factors in relation to blood triglyceride (TG) levels were found. Carriers of the A1 allele (A1A1 homozygotes plus A1A2 heterozygotes) were protected from TG increases by maltose intake (P int. = 0.023). Instead, A2A2 homozygotes were susceptible to TG rises through consumptions of total fat (P int. = 0.041), monounsaturated fatty acids (P int. = 0.001), and dietary cholesterol (P int. = 0.019). This study suggests that the interactions between DRD2/ANKK1 TaqIA polymorphism and dietary factors (sugar and fats) influence TG levels in diabetic patients.

Review: Chemosensing of nutrients and non-nutrients in the human and porcine gastrointestinal tract

The gastrointestinal tract (GIT) is an interface between the external and internal milieus that requires continuous monitoring for nutrients or pathogens and toxic chemicals. The study of the physiological/molecular mechanisms, mediating the responses to the monitoring of the GIT contents, has been referred to as chemosensory science. While most of the progress in this area of research has been obtained in laboratory rodents and humans, significant steps forward have also been reported in pigs. The objective of this review was to update the current knowledge on nutrient chemosensing in pigs in light of recent advances in humans and laboratory rodents. A second objective relates to informing the existence of nutrient sensors with their functionality, particularly linked to the gut peptides relevant to the onset/offset of appetite. Several cell types of the intestinal epithelium such as Paneth, goblet, tuft and enteroendocrine cells (EECs) contain subsets of chemosensory receptors also found on the tongue as part of the taste system. In particular, EECs show specific co-expression patterns between nutrient sensors and/or transceptors (transport proteins with sensing functions) and anorexigenic hormones such as cholecystokinin (CCK), peptide tyrosine tyrosine (PYY) or glucagon-like peptide-1 (GLP-1), amongst others. In addition, the administration of bitter compounds has an inhibitory effect on GIT motility and on appetite through GLP-1-, CCK-, ghrelin- and PYY-labelled EECs in the human small intestine and colon. Furthermore, the mammalian chemosensory system is the target of some bacterial metabolites. Recent studies on the human microbiome have discovered that commensal bacteria have developed strategies to stimulate chemosensory receptors and trigger host cellular functions. Finally, the study of gene polymorphisms related to nutrient sensors explains differences in food choices, food intake and appetite between individuals.

Hepatitis C virus clearance and less liver damage in patients with high cholesterol, low-density lipoprotein cholesterol and APOE ε4 allele

BACKGROUND

Cholesterol is related to improvements in the rate of sustained virological response and a robust immune response against the hepatitis C virus (HCV). APOE gene polymorphisms regulate cholesterol levels modifying the course of the HCV infection. The relationship between cholesterol, APOE alleles, and the outcome of HCV infection has not been evaluated in the admixed population of Mexico.

AIM

To investigate the role of APOE -ε2, -ε3, and -ε4 alleles and the metabolic profile in the outcome of HCV infection.

METHODS

A total of 299 treatment-naïve HCV patients were included in this retrospective study. Patients were stratified in chronic hepatitis C (CHC) (n = 206) and spontaneous clearance (SC) (n = 93). A clinical record was registered. Biochemical tests were assessed by dry chemistry assay. APOE genotypes were determined using a Real-Time polymerase chain reaction assay.

RESULTS

Total cholesterol, low-density lipoprotein cholesterol (LDL-c), triglycerides, and hypercholesterolemia were higher in SC than CHC patients as well as the frequency of the APOE ε4 allele (12.4% vs 7.3%). SC patients were overweight (54.8%). The ε4 allele was associated with SC (OR = 0.55, 95%CI: 0.31-0.98, P = 0.042) and mild fibrosis (F1-F2) in CHC patients (OR 0.091, 95%CI 0.01-0.75, P = 0.020). LDL-c ≥ 101.5 mg/dL (OR = 0.20, 95%CI: 0.10-0.41, P < 0.001) and BMI ≥ 26.6 kg/m2 (OR= 0.37, 95%CI: 0.18-0.76, P < 0.001) were associated with SC status; while ALT ≥ 50.5 IU/L was negatively associated (OR = 5.67, 95%CI: 2.69-11.97, P < 0.001).

CONCLUSION

In SC patients, the APOE ε4 allele and LDL-c conferred a protective effect in the course of the HCV infection in the context of excess body weight.

DRD2/ANKK1 TaqI A1 polymorphism associates with overconsumption of unhealthy foods and biochemical abnormalities in a Mexican population

PURPOSE

The dopamine receptor 2/ankyrin repeat domain and content kinase 1 (DRD2/ANKK1) TaqIA polymorphism (rs1800497) has been associated with rewarding behaviors. This study aimed to investigate the association of DRD2/ANKK1 TaqIA polymorphism with the dietary intake, the intake frequency of food groups and biochemical profile in Mexican mestizo subjects.

METHODS

A cross-sectional/analytical study with 276 Mexican subjects was performed. Dietary intake was assessed with a 24-h recall and a food frequency questionnaire (FFQ). An allelic discrimination assay evaluated DRD2/ANKK1 TaqIA genotypes. Anthropometric and biochemical data were evaluated.

RESULTS

Genotype frequencies were A1A1 (18.48%), A1A2 (45.29%) and A2A2 (36.23%). TaqI A1 allele carriers had a higher intake of carbohydrates (p = 0.038), meats (p = 0.005), fried dishes (p = 0.039), and sugars (p = 0.009). Male TaqI A1 carriers consumed more carbohydrates (p = 0.009) and meats (p = 0.018) while females consumed fewer legumes (p = 0.005). TaqI A1 carriers had glucose (p = 0.037) and triglycerides (p = 0.011) abnormalities. TaqI A1 was associated with higher risk of consumption of unhealthy foods such as fried dishes (OR 3.79, 95% CI 1.53-9.35, p = 0.002) and meats (OR 2.31, 95% CI 1.32-4.05, p = 0.003), and lower healthy foods (OR 1.89, 95% CI 1.04-3.29, p = 0.038). TaqI A1 allele was associated with risk of abnormal glucose, triglycerides, and VLDL levels (OR 2.148, 95% CI 1.068-4.322, p = 0.036; OR 1.999, 95% CI 1.194-3.348, p = 0.011; OR 2.021, 95% CI 1.203-3.392, p = 0.007), respectively.

CONCLUSIONS

The presence of the TaqI A1 allele in Mexicans is a genetic risk factor for detrimental dietary quality that may predispose to metabolic disturbances.

LEVEL OF EVIDENCE

Level III, case-control analytic study.

Taste Receptors in Upper Airway Innate Immunity

Taste receptors, first identified on the tongue, are best known for their role in guiding our dietary preferences. The expression of taste receptors for umami, sweet, and bitter have been demonstrated in tissues outside of the oral cavity, including in the airway, brain, gastrointestinal tract, and reproductive organs. The extra-oral taste receptor chemosensory pathways and the endogenous taste receptor ligands are generally unknown, but there is increasing data suggesting that taste receptors are involved in regulating some aspects of innate immunity, and may potentially control the composition of the nasal microbiome in healthy individuals or patients with upper respiratory diseases like chronic rhinosinusitis (CRS). For this reason, taste receptors may serve as potential therapeutic targets, providing alternatives to conventional antibiotics. This review focuses on the physiology of sweet (T1R) and bitter (T2R) taste receptors in the airway and their activation by secreted bacterial products. There is particular focus on T2R38 in sinonasal ciliated cells, as well as the sweet and bitter receptors found on specialized sinonasal solitary chemosensory cells. Additionally, this review explores the impact of genetic variations in these receptors on the differential susceptibility of patients to upper airway infections, such as CRS.

New insight into human sweet taste: a genome-wide association study of the perception and intake of sweet substances

BACKGROUND

Individual differences in human perception of sweetness are partly due to genetics; however, which genes are associated with the perception and the consumption of sweet substances remains unclear.

OBJECTIVE

The aim of this study was to verify previous reported associations within genes involved in the peripheral receptor systems (i.e., TAS1R2, TAS1R3, and GNAT3) and reveal novel loci.

METHODS

We performed genome-wide association scans (GWASs) of the perceived intensity of 2 sugars (glucose and fructose) and 2 high-potency sweeteners (neohesperidin dihydrochalcone and aspartame) in an Australian adolescent twin sample (n = 1757), and the perceived intensity and sweetness and the liking of sucrose in a US adult twin sample (n = 686). We further performed GWASs of the intake of total sugars (i.e., total grams of all dietary mono- and disaccharides per day) and sweets (i.e., handfuls of candies per day) in the UK Biobank sample (n = ≤174,424 white-British individuals). All participants from the 3 independent samples were of European ancestry.

RESULTS

We found a strong association between the intake of total sugars and the single nucleotide polymorphism rs11642841 within the FTO gene on chromosome 16 (P = 3.8 × 10-8) and many suggestive associations (P < 1.0 × 10-5) for each of the sweet perception and intake phenotypes. We showed genetic evidence for the involvement of the brain in both sweet taste perception and sugar intake. There was limited support for the associations with TAS1R2, TAS1R3, and GNAT3 in all 3 European samples.

CONCLUSIONS

Our findings indicate that genes additional to those involved in the peripheral receptor system are also associated with the sweet taste perception and intake of sweet-tasting foods. The functional potency of the genetic variants within TAS1R2, TAS1R3, and GNAT3 may be different between ethnic groups and this warrants further investigations.

Association between taste perception and adiposity in overweight or obese older subjects with metabolic syndrome and identification of novel taste-related genes

BACKGROUND

The relation between taste perception, diet, and adiposity remains controversial. Additionally, there is a lack of knowledge on the polymorphisms influencing taste given the scarcity of genome-wide association studies (GWASs) published.

OBJECTIVES

We studied the relation between perception of the basic tastes, i.e., sweet, salty, bitter, sour, and umami (separately and jointly in a "taste score"), and anthropometric measurements in older subjects with metabolic syndrome (MetS). GWASs were undertaken to identify genes associated with basic tastes and their score.

METHODS

Taste perception was cross-sectionally determined by challenging subjects (381 older individuals with MetS) with solutions (5 concentrations) of the basic tastes with the use of standard prototypical tastants (phenylthiocarbamide and 6-n-propylthiouracil, NaCl, sucrose, monopotassium glutamate, and citric acid, for bitter, salt, sweet, umami, and sour, respectively). Taste perception intensities were expressed on a scale. A total taste score was derived.

RESULTS

The total taste score was inversely associated with body weight, body mass index, and waist circumference (P < 0.05). Subjects having a total taste score higher than or equal to the median (11 points for concentration V) were less likely to be classified as obese than subjects below the median (OR: 0.36; 95% CI: 0.22, 0.59; P < 0.001). Associations were similar, albeit less strong, for some taste qualities. In the GWASs, the highest associations were for bitter taste (rs1726866-TAS2R38, with P = 7.74 × 10-18 for phenylthiocarbamide and P = 3.96 × 10-19 for 6-n-propylthiouracil). For other tastes, several single-nucleotide polymorphisms (SNPs) exceeded the P threshold of 1 × 10-5. However, the top-ranked SNPs independently explained a low percentage of taste variability, hence their use as single proxies for the association between taste perception and adiposity is limited.

CONCLUSIONS

We found a strong inverse association between greater taste perception and body weight, body mass index, and waist circumference in older subjects with MetS and identified some taste-related SNPs. It would be advantageous to identify additional genetic proxies for taste and to develop polygenic scores. Data used in this study were derived from the clinical trial PREDIMED PLUS at baseline, registered at http://www.isrctn.com as ISRCTN89898870.

Associations between olfactory pathway gene methylation marks, obesity features and dietary intakes

Background

Olfaction is an important sense influencing food preferences, appetite, and eating behaviors. This hypothesis-driven study aimed to assess associations between olfactory pathway gene methylation signatures, obesity features, and dietary intakes.

Methods

A nutriepigenomic analysis was conducted in 474 adults from the Methyl Epigenome Network Association (MENA) project. Anthropometric measurements, clinical data, and serum metabolic profiles of the study population were obtained from structured databases of the MENA cohorts. Habitual dietary intake was assessed using a validated semiquantitative food frequency questionnaire. DNA methylation was measured in circulating white blood cells by microarray (Infinium Human Methylation 450 K BeadChips). FDR values (p < 0.0001) were used to select those CpGs that showed the best correlation with body mass index (BMI) and waist circumference (WC). Pathway analyses involving the characterization of genes involved in the olfactory transduction system were performed using KEGG and pathDIP reference databases.

Results

Overall, 15 CpG sites at olfactory pathway genes were associated with BMI (p < 0.0001) and WC (p < 0.0001) after adjustments for potential confounding factors. Together, methylation levels at the15 CpG sites accounted for 22% and 20% of the variability in BMI and WC (r² = 0.219, p < 0.001, and r² = 0.204, p < 0.001, respectively). These genes encompassed olfactory receptors (OR4D2, OR51A7, OR2T34, and OR2Y1) and several downstream signaling molecules (SLC8A1, ANO2, PDE2A, CALML3, GNG7, CALML6, PRKG1, and CAMK2D), which significantly regulated odor detection and signal transduction processes within the complete olfactory cascade, as revealed by pathway enrichment analyses (p = 1.94 × 10^–10). Moreover, OR4D2 and OR2Y1 gene methylation patterns strongly correlated with daily intakes of total energy (p < 0.0001), carbohydrates (p < 0.0001), protein (p < 0.0001), and fat (p < 0.0001).

Conclusions

The results of this study suggest novel relationships between olfactory pathway gene methylation signatures, obesity indices, and dietary intakes.

Role of Endocannabinoids on Sweet Taste Perception, Food Preference, and Obesity-related Disorders

The prevalence of obesity and obesity-related disorders such as type 2 diabetes (T2D) and metabolic syndrome has increased significantly in the past decades, reaching epidemic levels and therefore becoming a major health issue worldwide. Chronic overeating of highly palatable foods is one of the main responsible aspects behind overweight. Food choice is driven by food preference, which is influenced by environmental and internal factors, from availability to rewarding properties of food. Consequently, the acquisition of a dietary habit that may lead to metabolic alterations is the result of a learning process in which many variables take place. From genetics to socioeconomic status, the response to food and how this food affects energy metabolism is heavily influenced, even before birth. In this work, we review how food preference is acquired and established, particularly as regards sweet taste; towards which flavors and tastes we are positively predisposed by our genetic background, our early experience, further lifestyle, and our surroundings; and, especially, the role that the endocannabinoid system (ECS) plays in all of this. Ultimately, we try to summarize why this system is relevant for health purposes and how this is linked to important aspects of eating behavior, as its function as a modulator of energy homeostasis affects, and is affected by, physiological responses directly associated with obesity.

High prevalence of nonalcoholic steatohepatitis and abnormal liver stiffness in a young and obese Mexican population

OBJECTIVE

To identify nonalcoholic steatohepatitis (NASH) and liver stiffness in Mexican subjects with different body mass index (BMI).

METHODS

A cross-sectional study was conducted in 505 adults. Risk for NASH was defined as the presence of one or more of the following biochemical and metabolic parameters (BMPs): fasting glucose ≥100 mg/dl, triglycerides (TG) ≥150 mg/dl, homeostatic model assessment of insulin resistance (HOMA-IR) ≥2.5, aspartate aminotransferase (AST) >54 IU/L and alanine aminotransferase (ALT) >42 IU/L. Body mass index measurement and nutritional assessment were performed by standard procedures. Liver fibrosis stage was determined by liver stiffness measurement using transitional elastography (TE) or by liver biopsy (LB).

RESULTS

Risk for NASH was 57% (290/505). Most BMPs values incremented by BMI category. Among 171 at-risk patients, 106 subjects were evaluated by TE and 65 subjects by LB. Abnormal liver stiffness (≥6.0 kPa) was prevalent in 54% (57/106) of the cases, whereas by LB, 91% (59/65) of patients with obesity had NASH and liver fibrosis. Furthermore, liver fibrosis was prevalent in 46% (6/13) in normal weight individuals, whereas 4.6% (3/65) of patients with a BMI ≥ 35 kg/m2 showed no histopathological abnormalities. Overall, 67.8% (116/171) of the patients had abnormal liver stiffness or NASH. The normal weight patients with liver damage consumed relatively a higher fat-rich diet compared to the other groups whereas the remaining subgroups shared a similar dietary pattern.

CONCLUSION

Young patients with overweight and obesity showed a high prevalence of altered BMPs related to abnormal liver stiffness assessed by TE and NASH by LB. Early diagnostic strategies are required to detect the risk for NASH and avoid further liver damage in populations with a rising prevalence of obesity by defining the risk factors involved in the onset and progression of NASH.

Taste receptor function

This chapter summarizes the available data about taste receptor functions and their role in perception of food with emphasis on the human system. In addition we illuminate the widespread presence of these receptors throughout the body and discuss some of their extraoral functions. Finally, we describe clinical aspects where taste receptor signaling could be relevant.

TAS1R1 and TAS1R3 Polymorphisms Relate to Energy and Protein-Rich Food Choices from a Buffet Meal Respectively

Eating behaviour in humans is a complex trait that involves sensory perception. Genetic variation in sensory systems is one of the factors influencing perception of foods. However, the extent that these genetic variations may determine food choices in a real meal scenario warrants further research. This study investigated how genetic variants of the umami taste receptor (TAS1R1/TAS1R3) related to consumption of umami-tasting foods. Thirty normal-weight adult subjects were offered “ad libitum” access to a variety of foods covering the full range of main taste-types for 40 min using a buffet meal arrangement. Buccal cell samples were collected and analysed for six single nucleotide polymorphisms (SNPs) reported previously related to the TAS1R1/TAS1R3 genes. Participants identified with the CC alleles of the TAS1R3 rs307355 and rs35744813 consumed significantly more protein from the buffet than T carriers. In addition, participants with GG genotype of the TAS1R1 SNP rs34160967 consumed more fat and calories as compared to the genotype group having the A alleles. In summary, these findings revealed a link between the SNPs variations of umami taster receptor gene and fat and protein intake from a buffet meal.

Bitter, Sweet, Salty, Sour and Umami Taste Perception Decreases with Age: Sex-Specific Analysis, Modulation by Genetic Variants and Taste-Preference Associations in 18 to 80 Year-Old Subjects

There is growing interest in relating taste perception to diet and healthy aging. However, there is still limited information on the influence of age, sex and genetics on taste acuity as well as on the relationship between taste perception and taste preferences. We have analysed the influence of age on the intensity rating of the five basic tastes: sweet, salty, bitter, sour and umami (separately and jointly in a “total taste score”) and their modulation by sex and genetics in a relatively healthy population (men and women) aged 18–80 years (n = 1020 Caucasian European participants). Taste perception was determined by challenging subjects with solutions of the five basic tastes using standard prototypical tastants (6-n-propylthiouracil (PROP), NaCl, sucrose, monopotassium glutamate and citric acid) at 5 increasing concentrations (I to V). We also measured taste preferences and determined the polymorphisms of the genes taste 2 receptor member 38 (TAS2R38), taste 1 receptor member 2 (TAS2R38) and sodium channel epithelial 1 beta subunit (SCNN1B), as TAS2R38-rs713598, TAS1R2-rs35874116 and SCNN1B-rs239345 respectively. We found a statistically significant decrease in taste perception (“total taste score”) with increasing age for all the concentrations analysed. This association was stronger for the higher concentrations (p = 0.028; p = 0.012; p = 0.005; p = 4.20 × 10⁻⁵ and p = 1.48 × 10⁻⁷, for I to V in the multivariable-adjusted models). When we analysed taste qualities (using concentration V), the intensity rating of all the 5 tastes was diminished with age (p < 0.05 for all). This inverse association differed depending on the test quality, being higher for bitter (PROP) and sour. Women perceived taste significantly more intense than men (p = 1.4 × 10⁻⁸ for total taste score). However, there were differences depending on the taste, umami being the lowest (p = 0.069). There was a complex association between the ability to perceive a taste and the preference for the same. Significant associations were, nevertheless, found between a higher perception of sour taste and a higher preference for it in women. In contrast, the higher perception of sweet was significantly associated with a higher preference for bitter in both, men and women. The TAS2R38-rs713598 was strongly associated with bitter (PROP) taste (p = 1.38 × 10⁻⁵⁰), having a significant interaction with sex (p = 0.030). The TAS1R2-rs35874116 was not significantly associated with sweet, whereas the SCNN1B-rs239345 was associated (p = 0.040) with salty taste. In conclusion, the inverse association between age and perceived taste intensity as well as the additional influence of sex and some genetic polymorphisms give rise to large inter-individual differences in taste perception and taste preferences that should be taken into account in future studies and for applications in precision nutrition for healthy aging.

The Relationship between Single Nucleotide Polymorphisms in Taste Receptor Genes, Taste Function and Dietary Intake in Preschool-Aged Children and Adults in the Guelph Family Health Study

Taste is a fundamental determinant of food selection, and inter-individual variations in taste perception may be important risk factors for poor eating habits and obesity. Characterizing differences in taste perception and their influences on dietary intake may lead to an improved understanding of obesity risk and a potential to develop personalized nutrition recommendations. This study explored associations between 93 single nucleotide polymorphisms (SNPs) in sweet, fat, bitter, salt, sour, and umami taste receptors and psychophysical measures of taste. Forty-four families from the Guelph Family Health Study participated, including 60 children and 65 adults. Saliva was collected for genetic analysis and parents completed a three-day food record for their children. Parents underwent a test for suprathreshold sensitivity (ST) and taste preference (PR) for sweet, fat, salt, umami, and sour as well as a phenylthiocarbamide (PTC) taste status test. Children underwent PR tests and a PTC taste status test. Analysis of SNPs and psychophysical measures of taste yielded 23 significant associations in parents and 11 in children. After adjusting for multiple hypothesis testing, the rs713598 in the TAS2R38 bitter taste receptor gene and rs236514 in the KCNJ2 sour taste-associated gene remained significantly associated with PTC ST and sour PR in parents, respectively. In children, rs173135 in KCNJ2 and rs4790522 in the TRPV1 salt taste-associated gene remained significantly associated with sour and salt taste PRs, respectively. A multiple trait analysis of PR and nutrient composition of diet in the children revealed that rs9701796 in the TAS1R2 sweet taste receptor gene was associated with both sweet PR and percent energy from added sugar in the diet. These findings provide evidence that for bitter, sour, salt, and sweet taste, certain genetic variants are associated with taste function and may be implicated in eating patterns. (Support was provided by the Ontario Ministry of Agriculture, Food, and Rural Affairs).

Dopamine D2 receptor polymorphism (C957T) is associated with sugar consumption and triglyceride levels in West Mexicans

Genetic variations in the dopamine receptor D2 (DRD2) may alter dopamine signaling and modify the rewarding effects of food. This study aimed to analyze the association of the C957T DRD2 polymorphism with sugar consumption in West Mexican subjects. In a cross-sectional and analytical study, a total of 215 Mexican subjects were enrolled. DRD2 genotyping was performed by an allelic discrimination assay. Habitual dietary intake and the biochemical profile were evaluated. Genotype frequencies of the C957T DRD2 polymorphism were CC (12.1%), CT (40.9%) and TT (47.0%). Carriers of the CC genotype had a higher intake of sugar (g/day) than heterozygotes (67.4 g vs. 41.3 g, p = 0.001) and TT homozygotes (67.4 g vs. 45.2 g, p = 0.004). Also, the habitual consumption of soda (daily or at least 3 times per week) was more frequent among CC genotype carriers compared with heterozygotes (81% vs. 51%, p = 7.5 × 10^-6) and TT homozygotes (81% vs. 57%, p = 2.4 × 10^-4). Furthermore, the CC genotype was associated with elevated serum triglyceride levels (>150 mg/dL) than the CT genotype (OR = 2.80, 95% CI 1.08-7.24, p = 0.034). In conclusion, our results suggest a genetic background associated with sugar consumption among West Mexicans, which may contribute to increases in serum triglyceride levels.

Percepción del gusto como factor de riesgo para obesidad infantil

Objetivo. Describir el papel de la percepción del gusto como factor de riesgo para el desarrollo de obesidad en niños. Material y métodos. Se realizó una búsqueda inicial de artículos científicos publicados en PubMed entre el 1 de enero de 2011 y el 20 de marzo de 2016 para el tema sobrepeso y obesidad en niños de entre 0 y 12 años. Los algoritmos utilizados fueron (Obesity OR Overweight) AND Taste perception, Satiation, Satiety response, Appetite, Appetite regulation, Habitua­tion, Taste receptors [MeSH] y PROP phenotype. En búsquedas subsecuentes se incluyeron artículos previos y posteriores a la fecha de la búsqueda general (hasta mayo 2018). Re­sultados. Las preferencias por los sabores inician desde la gestación, por lo que los niños que son expuestos a sabores dulces en etapas tempranas de la infancia aumentan su riesgo de habituación a éstos. Asimismo, las experiencias hedónicas dadas por la ingestión de alimentos y bebidas dulces refuerzan el consumo de estos alimentos, lo que propicia la selección de productos o bebidas de sabor dulce en etapas posteriores. Estas preferencias se han asociado con el desarrollo de obe­sidad en los niños. Las variantes genéticas relacionadas con la percepción del gusto también pueden contribuir a la selección de cierto tipo de alimentos. Sin embargo, su relación con una mayor ingestión de energía, así como con un mayor peso corporal, ha sido poco explorada y ha mostrado resultados inconsistentes. Conclusiones. Se requiere más evidencia para entender las interacciones ambientales y genéticas de la percepción del gusto, a fin de considerarlo un factor más en las intervenciones de política pública.

Taste receptors in the upper airway

Taste receptors were named for their originally-identified expression on the tongue and role in the sensation of taste (gustation). They are now known to be involved in many chemosensory processes outside the tongue. Expression of the receptors for bitter, sweet, and umami was recently identified in many organs, including the brain, airway, gastrointestinal tract, and reproductive systems. We do not yet know the full roles of these receptors in all of these tissues, nor do we know all of the endogenous ligands that activate them. However, taste receptors are emerging as potentially important therapeutic targets. Moreover, they may mediate some off target effects of drugs, as many medications in common clinical use are known to be bitter. The focus of this review is on recent basic and clinical data describing the expression of bitter (T2R) and sweet (T1R) receptors in the airway and their activation by secreted bacterial compounds. These receptors play important roles in innate immune nitric oxide production and antimicrobial peptide secretion, and may be useful targets for stimulating immune responses in the upper respiratory tract via topical therapies. Moreover, genetic variation in these receptors may play a role in the differential susceptibility of patients to certain types of respiratory infections as well as to differential outcomes in patients with chronic rhinosinusitis (CRS). CRS is a syndrome of chronic upper respiratory infection and inflammation and has a significant detrimental impact on patient quality of life. CRS treatment accounts for approximately 20% of adult antibiotic prescriptions and is thus a large driver of the public health crisis of antibiotic resistance. Taste receptors represent a novel class of therapeutic target to potentially stimulate endogenous immune responses and treat CRS patients without conventional antibiotics.

Nutrient-Sensing Biology in Mammals and Birds

Nutrient-sensing mechanisms have emerged as the fringe articulating nutritional needs with dietary choices. Carbohydrate, amino acid, fatty acid, mineral, and water-sensing receptors are highly conserved across mammals and birds, consisting of a repertoire of 22 genes known to date. In contrast, bitter receptors are highly divergent and have a high incidence of polymorphisms within and between mammals and birds and are involved in the adaptation of species to specific environments. In addition, the expression of nutrient-sensing genes outside the oral cavity seems to mediate the required decision-making dialogue between the gut and the brain by translating exogenous chemical stimuli into neuronal inputs, and vice versa, to translate the endogenous signals relevant to the nutritional status into specific appetites and the control of feed intake. The relevance of these sensors in nondigestive systems has uncovered fascinating potential as pharmacological targets relevant to respiratory and cardiovascular diseases.

Tailoring Nutritional Advice for Mexicans Based on Prevalence Profiles of Diet-Related Adaptive Gene Polymorphisms

Diet-related adaptive gene (DRAG) polymorphisms identified in specific populations are associated with chronic disorders in carriers of the adaptive alleles due to changes in dietary and lifestyle patterns in recent times. Mexico’s population is comprised of Amerindians (AM) and Mestizos who have variable AM, European (EUR) and African genetic ancestry and an increased risk of nutrition-related chronic diseases. Nutritional advice based on the Mexican genome and the traditional food culture is needed to develop preventive and therapeutic strategies. Therefore, we aimed to provide a prevalence profile of several DRAG polymorphisms in the Mexican population, including Central West (CW) Mexico subpopulations. Geographic heat maps were built using ArcGIS10 (Esri, Redlands, CA, USA) software, based on the published data of the MTHFR C677T (rs1801133), ABCA1 Arg230Cys (rs9282541), APOE T388C (rs429358)/C526T (rs7412), LCT C-13910T (rs4988235) polymorphisms and AMY1 copy number variation (CNV). Also, new data obtained by allelic discrimination-real-time polymerase chain reaction (RT-PCR) assays for the MTHFR, ABCA1, and APOE polymorphisms as well as the AMY1 CNV in the CW Mexico subpopulations with different proportions of AM and EUR ancestry were included. In the CW region, the highest frequency of the MTHFR 677T, ABCA1 230C and APOE ε4 adaptive alleles was observed in the AM groups, followed by Mestizos with intermediate AM ancestry. The LCT-13910T allele frequency was highest in Mestizos-EUR but extremely low in AM, while the AMY1 diploid copy number was 6.82 ± 3.3 copies. Overall, the heat maps showed a heterogeneous distribution of the DRAG polymorphisms, in which the AM groups revealed the highest frequencies of the adaptive alleles followed by Mestizos. Given these genetic differences, genome-based nutritional advice should be tailored in a regionalized and individualized manner according to the available foods and Mexican traditional food culture that may lead to a healthier dietary pattern.

Salivary leptin and TAS1R2/TAS1R3 polymorphisms are related to sweet taste sensitivity and carbohydrate intake from a buffet meal in healthy young adults

The influence of sweet taste sensitivity on food intake is not well understood. We investigated the involvement of salivary leptin and SNP of the sweet taste receptor genes (TAS1R2/TAS1R3) on sweet taste sensitivity, sensory-specific satiety (SSS) and macronutrient intake in healthy human adults. In all, nineteen high sweet sensitivity (HS) and eleven low sweet sensitivity (LS) subjects were classified based on the sweetness perception of one solution (9 mm sucrose) forced-choice triangle test. All participants completed a randomised crossover design experiment where they consumed one of three iso-energetic soup preloads differing in primary taste quality (sweet, non-sweet taste-control or no-taste energy-control). A period of 1 h after the preload, participants were offered a buffet meal consisting of foods varying in taste (sweet or non-sweet) and fat content. Subjective measures included hunger/fullness and SSS for sweetness. Saliva and buccal cells were collected to measure leptin level and to study the TAS1R2/TAS1R3 specific SNP, respectively. Salivary leptin concentrations were significantly higher in LS than HS participants (P<0·05). In addition, HS showed stronger sweet SSS compared with LH participants (P<0·05), and consumed less carbohydrate (% energy) and more non-sweet foods than LS (P<0·01 and P<0·05, respectively). Alleles from each TAS1R2 locus (GG compared with AA alleles of rs12033832, and CT/CC compared with TT alleles of rs35874116) were related to higher consumption of carbohydrates (% energy) and higher amount of sweet foods, respectively (P<0·05). In contrast, no associations were found for the TAS1R3 alleles. These results contribute to understand the links between taste sensitivity, macronutrient appetite and food consumption.

DNA methylation patterns at sweet taste transducing genes are associated with BMI and carbohydrate intake in an adult population

Individual differences in taste perception may influence appetite, dietary intakes, and subsequently, disease risk. Correlations of DNA methylation patterns at taste transducing genes with BMI and dietary intakes were studied. A nutriepigenomic analysis within the Methyl Epigenome Network Association (MENA) project was conducted in 474 adults. DNA methylation in peripheral white blood cells was analyzed by a microarray approach. KEGG pathway analyses were performed concerning the characterization and discrimination of genes involved in the taste transduction pathway. Adjusted FDR values (p < 0.0001) were used to select those CpGs that showed best correlation with BMI. A total of 29 CpGs at taste transducing genes met the FDR criteria. However, only 12 CpGs remained statistically significant after linear regression analyses adjusted for age and sex. These included cg15743657 (TAS1R2), cg02743674 (TRPM5), cg01790523 (SCN9A), cg15947487 (CALHM1), cg11658986 (ADCY6), cg04149773 (ADCY6), cg02841941 (P2RY1), cg02315111 (P2RX2), cg08273233 (HTR1E), cg14523238 (GABBR2), cg12315353 (GABBR1) and cg05579652 (CACNA1C). Interestingly, most of them were implicated in the sweet taste signaling pathway, except CACNA1C (sour taste). In addition, TAS1R2 methylation at cg15743657 was strongly correlated with total energy (p < 0.0001) and carbohydrate intakes (p < 0.0001). This study suggests that methylation in genes related to sweet taste could be an epigenetic mechanism associated with obesity.

Guide for Current Nutrigenetic, Nutrigenomic, and Nutriepigenetic Approaches for Precision Nutrition Involving the Prevention and Management of Chronic Diseases Associated with Obesity

Chronic diseases, including obesity, are major causes of morbidity and mortality in most countries. The adverse impacts of obesity and associated comorbidities on health remain a major concern due to the lack of effective interventions for prevention and management. Precision nutrition is an emerging therapeutic approach that takes into account an individual's genetic and epigenetic information, as well as age, gender, or particular physiopathological status. Advances in genomic sciences are contributing to a better understanding of the role of genetic variants and epigenetic signatures as well as gene expression patterns in the development of diverse chronic conditions, and how they may modify therapeutic responses. This knowledge has led to the search for genetic and epigenetic biomarkers to predict the risk of developing chronic diseases and personalizing their prevention and treatment. Additionally, original nutritional interventions based on nutrients and bioactive dietary compounds that can modify epigenetic marks and gene expression have been implemented. Although caution must be exercised, these scientific insights are paving the way for the design of innovative strategies for the control of chronic diseases accompanying obesity. This document provides a number of examples of the huge potential of understanding nutrigenetic, nutrigenomic, and nutriepigenetic roles in precision nutrition.