Combination of ACTN3 R577X and ACE I/D polymorphisms as a tool for prediction of obesity risk in children

The frequency of the ACE I/D polymorphism in South America: a systematic review and meta-analysis

Angiotensin-converting enzyme (ACE) is a key component of the renin-angiotensin system and plays an important role in homeostasis and maintenance of blood pressure. However, little is known about allele and genotypic frequencies, as well as phenotypic characteristics associated with ACE polymorphism genotypes in South American populations. This study aimed to verify the allelic predominance and genotype frequency of ACE I/D polymorphism in South America and its association with the main diseases and related conditions. We conducted a systematic review considering studies published in the last 25 years available in PubMed, Scielo, LILACS, LIPECS, Coleciona SUS, CUMED, BINACIS, IBECS, and MEDLINE databases, resulting in the inclusion of 121 studies. Quality of the studies was assessed according to the Strengthening the Reporting of Genetic Association (STREGA) guidelines. We mapped the frequency of the ACE I/D polymorphism in South American populations. 8,856 (32.1%) subjects were DD, 13,050 were ID (47.4%), and 5,644 were II (20.5%) carriers. The main associated conditions included systemic arterial hypertension and other cardiovascular conditions, cardiorespiratory or respiratory characteristics, physical activity level, kidney conditions, aging-related diseases, as well as different types of cancers and metabolic conditions. 61.1% of the studies found no significant association between the respective conditions investigated and the ACE I/D polymorphism. Considering DD genotype or D allele, 21.5% of the studies observed negative and 4.9% positive outcomes. Regarding ID genotype, 4.1% of the studies identified negative and 0.8% positive outcomes, and for II genotype or I allele, 4.1% of the results had negative and 10.7% positive associations.

Association of сarriage of the rs4646994 polymorphism of the ACE gene with obesity and androgen deficiency in men

BACKGROUND: Obesity and androgen deficiency (AnD) are characterized by similar disturbances in metabolic parameters, the presence of signs of insulin resistance, metabolic syndrome, the risk of developing cardiovascular diseases (CVD) and vascular complications. These facts indicate the possibility of the presence of common mechanisms that determine the predisposition to the development of obesity and AnD, which may include genetic factors, in particular, the rs4646994 polymorphism of the ACE gene, which, according to recent data, is associated with the risk of developing CVD, hypertension, and obesity.

AIM: To study the association of the carriage of polymorphic variants of the rs4646994 locus of the ACE gene with the features of anthropometric and androgenic status in men.

MATERIALS AND METHODS: In the period from April 2020 to October 2021 there were observed male patients aged 18–75 years old, who were hospitalized in a therapeutic hospital because of comorbid somatic pathology (hypertension, coronary heart disease, dorsopathy, vegetative-vascular dystonia, gastroesophageal reflux disease, and others). Anthropometry, a study of the content of hormones of the reproductive system in the blood serum using enzyme-linked immunosorbent assay (ELISA), as well as a genetic study for the carriage of polymorphic variants of the rs4646994 locus of the ACE gene by the polymerase chain reaction (PCR) method, followed by electrophoresis of PCR products, were carried out. 

RESULTS: 82 patients took part in research. According to the results of genetic analysis, 17 people were assigned to the group of homozygotes for the wild type (I/I, G1), 41 people were assigned to the group of heterozygotes (I/D, G2), and 41 people were assigned to the group of homozygotes for the mutant allele (D/D, G3) 24 people. Body weight, chest circumference, waist and hips, body mass index in patients carrying the D allele of the rs4646994 polymorphism were statistically significantly higher than in I/I homozygotes. Differences in hormonal status also turned out to be statistically significant: patients from G1 compared with G2 and G3 had higher levels of total testosterone; from G1 compared to G3 — a higher level of free testosterone.

CONCLUSION: An association of the carriage of the D allele of the rs4646994 polymorphic locus of the ACE gene with overweight and ADI was revealed.

The ACTN3 R577X polymorphism is associated with metabolic alterations in a sex-dependent manner in subjects from western Mexico

BACKGROUND

The ACTN3 gene is primarily expressed in fast skeletal muscle fibres. A common nonsense polymorphism in this gene is ACTN3 R577X (rs1815739), which causes an absolute deficiency of α-actinin-3 protein and alterations in muscle metabolism. Considering metabolic alterations are influenced by nutrition and genetic factors, as well as lifestyle factors, we hypothesise a possible association of the ACTN3 R577X polymorphism with metabolic alterations.

METHODS

In this cross-sectional study, 397 adults met the inclusion criteria. Body composition was measured by electrical bioimpedance. Dietary data were analysed using Nutritionist Pro™ software. Biochemical variables were determined by dry chemistry. Genomic DNA was extracted from peripheral leukocytes and genotyping of the ACTN3 R577X polymorphism was determined by allelic discrimination using TaqMan probes. The statistical analyses were performed using SPSS statistical software. p < 0.05 was considered statistically significant.

RESULTS

The ACTN3 577XX genotype was associated with high glucose, triglyceride and very low density lipoprotein-cholesterol levels and a higher frequency of hypertriglyceridaemia and insulin resistance in women. In males, the genetic variant showed a trend towards significance for insulin resistance.

CONCLUSIONS

The ACTN3 R577X polymorphism was associated with metabolic alterations in women and a tendency was observed in men variant carriers. Thus, this common genetic variant could be implicated in the development of chronic metabolic diseases.