RESUMEN
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.
RESUMEN
BACKGROUND: The aging population is growing faster than any other age group worldwide. Associated with aging, the prevalence of overweight and obesity is a potential risk factor for the development and aggravation of numerous pathologies. A genetic factor often associated with obesity is the fat mass and obesity-associated (FTO) (rs9939609) gene polymorphism, which has been extensively investigated in children, young, and adults. However, few studies have been carried out on the older population. This review aimed to verify the influence of the FTO (rs9939609) gene polymorphism on the body composition of the older population. METHODS: We conducted a systematic review and meta-analysis on PubMed, Scielo, and LILACS databases. Statistical analysis for meta-analysis was performed using mean values of Body Mass Index (BMI) and standard deviations. RESULTS: The results did not show significant differences between FTO genotypes and BMI values (-0.32, 95% CI -0.45 to -0.19, I2 = 0%, p = 0.52). However, 59% of the studies identified some influence on body composition, obesity, or comorbidities. CONCLUSION: Few publications verify FTO polymorphism effects on specific groups of the older population, suggesting a reduction in the influence of this gene on the BMI with advancing age. However, we believe that more controlled studies in older populations should be performed.