FTO and ADRB2 Genetic Polymorphisms Are Risk Factors for Earlier Excessive Gestational Weight Gain in Pregnant Women with Pregestational Diabetes Mellitus: Results of a Randomized Nutrigenetic Trial

Gestational Weight Gain: Is the Role of Genetic Variants a Determinant? A Review

Excessive or insufficient gestational weight gain (GWG) leads to diverse adverse maternal and neonatal outcomes. There is evidence that pregestational body mass index (pBMI) plays a role in GWG, but no genetic cause has been identified. In this review, we aim to analyze genotype variants associated with GWG. Results: We identified seven genotype variants that may be involved in GWG regulation that were analyzed in studies carried out in Brazil, Romania, the USA, Turkey, Ukraine, and Canada. Some genetic variants were only associated with GWG in certain races or depending on the pBMI. In women who were obese or overweight before gestation, some genetic variants were associated with GWG. Environmental and genetic factors together showed a greater association with GWG than genetic factors alone; for example, type of diet was observed to have a significant influence. Conclusions: We found little scientific evidence of an association between genotype variants in countries with a high prevalence of women of reproductive age who are overweight and obese, such as in Latin America. GWG may be more dependent on environmental factors than genetic variants. We suggest a deeper study of genetic variants, cytokines, and their possible association with GWG, always with the respective control of potential cofounding factors, such as pBMI, diet, and race.

Understanding and applying gene-environment interactions: a guide for nutrition professionals with an emphasis on integration in African research settings

Noncommunicable diseases (NCDs) are influenced by the interplay between genetics and environmental exposures, particularly diet. However, many healthcare professionals, including nutritionists and dietitians, have limited genetic background and, therefore, they may lack understanding of gene-environment interactions (GxEs) studies. Even researchers deeply involved in nutrition studies, but with a focus elsewhere, can struggle to interpret, evaluate, and conduct GxE studies. There is an urgent need to study African populations that bear a heavy burden of NCDs, demonstrate unique genetic variability, and have cultural practices resulting in distinctive environmental exposures compared with Europeans or Americans, who are studied more. Although diverse and rapidly changing environments, as well as the high genetic variability of Africans and difference in linkage disequilibrium (ie, certain gene variants are inherited together more often than expected by chance), provide unparalleled potential to investigate the omics fields, only a small percentage of studies come from Africa. Furthermore, research evidence lags behind the practices of companies offering genetic testing for personalized medicine and nutrition. We need to generate more evidence on GxEs that also considers continental African populations to be able to prevent unethical practices and enable tailored treatments. This review aims to introduce nutrition professionals to genetics terms and valid methods to investigate GxEs and their challenges, and proposes ways to improve quality and reproducibility. The review also provides insight into the potential contributions of nutrigenetics and nutrigenomics to the healthcare sphere, addresses direct-to-consumer genetic testing, and concludes by offering insights into the field's future, including advanced technologies like artificial intelligence and machine learning.

Mechanisms and Physiological Roles of Polymorphisms in Gestational Diabetes Mellitus

Gestational diabetes mellitus (GDM) is a significant pregnancy complication linked to perinatal complications and an elevated risk of future metabolic disorders for both mothers and their children. GDM is diagnosed when women without prior diabetes develop chronic hyperglycemia due to β-cell dysfunction during gestation. Global research focuses on the association between GDM and single nucleotide polymorphisms (SNPs) and aims to enhance our understanding of GDM's pathogenesis, predict its risk, and guide patient management. This review offers a summary of various SNPs linked to a heightened risk of GDM and explores their biological mechanisms within the tissues implicated in the development of the condition.

Reproductive risk factors across the female lifecourse and later metabolic health

Metabolic health is characterized by optimal blood glucose, lipids, cholesterol, blood pressure, and adiposity. Alterations in these characteristics may lead to the development of type 2 diabetes mellitus or dyslipidemia. Recent evidence suggests that female reproductive characteristics may be overlooked as risk factors that contribute to later metabolic dysfunction. These reproductive traits include the age at menarche, menstrual irregularity, the development of polycystic ovary syndrome, gestational weight change, gestational dysglycemia and dyslipidemia, and the severity and timing of menopausal symptoms. These risk factors may themselves be markers of future dysfunction or may be explained by shared underlying etiologies that promote long-term disease development. Disentangling underlying relationships and identifying potentially modifiable characteristics have an important bearing on therapeutic lifestyle modifications that could ease long-term metabolic burden. Further research that better characterizes associations between reproductive characteristics and metabolic health, clarifies underlying etiologies, and identifies indicators for clinical application is warranted in the prevention and management of metabolic dysfunction.

Role of beta-2 adrenergic receptor polymorphism (rs1042714) on body weight and glucose metabolism response to a meal-replacement hypocaloric diet

OBJECTIVES

The beta-2 adrenergic receptor (ADRB2) is involved in energy balance regulation. The objective of our study was to evaluate the role of the rs1042714 genetic variant of ADRB2 gene on weight loss, body composition, and metabolic changes secondary to partial meal replacement (pMR) hypocaloric diet in women with obesity.

METHODS

We conducted an interventional study in 95 premenopausal women with body mass index ≥ 35 kg/m2. The subjects received two intakes per day of a normocaloric hyperproteic formula during 12 wk of a pMR diet. Body weight, body mass index, fat mass, waist circumference, lipid profile, fasting insulin levels, and homeostasis model assessment for insulin resistance were determined. All patients were genotyped rs1042714 and evaluated in a dominant model (CC versus CG + GG).

RESULTS

Genotype frequencies were 31 (37.3%), 38 (45.8%), and 14 (16.9%) for the CC, CG, and GG genotypes, respectively. We found significant interaction effects between ADRB2 variant and pMR-induced changes (CC versus CG + GG) on body weight (-7.1 ± 0.3 versus -13.5 ± 0.5 kg; P = 0.03), body mass index (-0.9 ± 0.1 versus -1.2 ± 0.2 kg/m2; P = 0.03), fat mass (-4.9 ± 0.5 versus -10.2 ±1.2 kg; P = 0.01), waist circumference (-5.1 ± 0.2 versus -10.1 ± 1.9 cm; P = 0.03), glucose (-5.1 ± 1.3 versus -12.5 ± 2.5 mg/dL; P = 0.03), total cholesterol (-18.1 ± 9.3 versus -33.5 ± 4.5 mg/dL; P = 0.03), low-density lipoprotein cholesterol (-9.1 ± 5.3 versus -24.5 ± 4.1 mg/dL; P = 0.04), triacylglycerol levels (-6.1 ± 5.3 versus -31.5 ± 9.5 mg/dL; P = 0.04), fasting insulin levels (-1.8 ± 0.3 versus -6.3 ± 0.5 IU/L; P = 0.03), and homeostasis model assessment for insulin resistance (-0.6 ± 0.3 versus -1.9 ± 0.5 U; P = 0.03). The odds ratio to improve alteration in glucose metabolism adjusted by age and weight loss throughout the study was 0.26 (95% CI, 0.07-0.95; P = 0.02) in G allele carriers.

CONCLUSIONS

The G allele of rs1042714 predicts the magnitude of weight loss resulting from a pMR diet. These adiposity improvements produce a better improvement of insulin resistance and percentage of impaired glucose metabolism in G allele carriers.

Genetic variant panel allows predicting both obesity risk, and efficacy of procedures and diet in weight loss

Purpose

Obesity is a multifactorial condition with a relevant genetic correlation. Recent advances in genomic research have identified several single nucleotide polymorphisms (SNPs) in genes such as FTO, MCM6, HLA, and MC4R, associated with obesity. This study aimed to evaluate the association of 102 SNPs with BMI and weight loss treatment response in a multi-ethnic population.

Methods

The study analyzed 9,372 patients for the correlation between SNPs and BMI (dataset A). The correlation between SNP and weight loss was accessed in 474 patients undergoing different treatments (dataset B). Patients in dataset B were further divided into 3 categories based on the type of intervention: dietary therapy, intragastric balloon procedures, or surgeries. SNP association analysis and multiple models of inheritance were performed.

Results

In dataset A, ten SNPs, including rs9939609 (FTO), rs4988235 (MCM6), and rs2395182 (HLA), were significantly associated with increased BMI. Additionally, other four SNPs, rs7903146 (TCF7L2), (rs6511720), rs5400 (SLC2A2), and rs7498665 (SH2B1), showed sex-specific correlation. For dataset B, SNPs rs2016520 (PPAR-Delta) and rs2419621 (ACSL5) demonstrated significant correlation with weight loss for all treatment types. In patients who adhered to dietary therapy, SNPs rs6544713 (ABCG8) and rs762551 (CYP1A2) were strongly correlated with weight loss. Patients undergoing surgical or endoscopic procedures exhibited differential correlations with several SNPs, including rs1801725 (CASR) and rs12970134 (MC4R), and weight loss.

Conclusion

This study provides valuable insights into the genetic factors influencing BMI and weight loss response to different treatments. The findings highlight the potential for personalized weight management approaches based on individual genetic profiles.

A Pilot Study of Dietetic, Phenotypic, and Genotypic Features Influencing Hypertensive Disorders of Pregnancy in Women with Pregestational Diabetes Mellitus

Hypertensive disorders of pregnancy (HDP) are a leading cause of maternal and perinatal morbimortality. Dietetic, phenotypic, and genotypic factors influencing HDP were analyzed during a nutrigenetic trial in Rio de Janeiro, Brazil (2016-2020). Pregnant women with pregestational diabetes mellitus (n = 70) were randomly assigned to a traditional or DASH diet group. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured during prenatal visits and HDP were diagnosed using international criteria. Phenotypic data were obtained from medical records and personal interviews. Genotyping for FTO and ADRB2 polymorphisms used RT-PCR. Linear mixed-effect models and time-to-event analyses were performed. The variables with significant effect on the risk for progression to HDP were: black skin color (adjusted hazard ratio [aHR] 8.63, p = 0.01), preeclampsia in previous pregnancy (aHR 11.66, p < 0.01), SBP ≥ 114 mmHg in the third trimester (aHR 5.56, p 0.04), DBP ≥ 70 mmHg in the first trimester (aHR 70.15, p = 0.03), mean blood pressure > 100 mmHg (aHR 18.42, p = 0.03), and HbA1c ≥ 6.41% in the third trimester (aHR 4.76, p = 0.03). Dietetic and genotypic features had no significant effect on the outcome, although there was limited statistical power to test both.