👤 Raquel Rodríguez-López

MC4R gene is a hypothalamic satiety control mediator in which mutations cause a monogenic form of obesity. The aim of this study was to perform a genetic screening to identify variations in the entire region of MC4R gene. A total of 236 unrelated and severely obese patients (BMI ≥ 40 kg/m Show less

At least 52 genetic loci were associated with obesity-related traits. However, little is known about the genetic basis of obesity among children. This study aims to test whether 10 polymorphisms in obesity-related genes methionine sulfoxide reductase A (MSRA), transcription factor AP-2 beta (TFAP2B), melanocortin 4 receptor (MC4R), neurexin 3 (NRXN3), peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PPARGC1A), transmembrane protein 18 (TMEM18), homolog of S. cerevisiae Sec16 (SEC16B), homeobox B5 (HOXB5) and olfactomedin 4 (OLFM4) are associated with the risk of obesity in Portuguese children. A total of 730 children aging from 6 to 12 years old, recruited randomly from public schools in Portugal, were analysed. Anthropometric measurements were obtained and children were classified into three phenotypic groups, normal weight (n=256), overweight (n=320) and obese (n=154), according to the International Obesity Task Force cutoffs. Polymorphisms were genotyped by allelic discrimination TaqMan assays. The MC4R rs12970134 polymorphism was nominally associated with body mass index (BMI) (P=0.035), BMI Z-score (P=0.043) and waist circumference (P=0.020), and borderline associated with weight (P=0.053). Near nominal associations were also found for the PPARGC1A rs8192678 polymorphism with weight (P=0.061), and for the MSRA rs545854 polymorphism with BMI (P=0.055) and BMI Z-score (P=0.056). Furthermore, logistic regression showed that MC4R rs12970134 and TFAP2B rs987237 were nominally, respectively, associated (P=0.029) and borderline associated (P=0.056) with the obese phenotype. This study highlighted the possible association of MC4R, PPARGC1A, MSRA and TFAP2B polymorphisms with several obesity-related traits in a sample of Portuguese children. The two significant associated TFAP2B rs987237 and MC4R rs12970134 polymorphisms showed an opposite direction of effect to that in the original reports. Show less

The objective of this study was the description of a valid genetic risk score (GRS) to predict individuals with high susceptibility to childhood overweight by their genetic profiles. Case-control study including a group of children with high-risk familial predisposition to morbid obesity. Birth cohort from general population constituted the validation sample. For the discovery sample, 218 children with non-syndromic obesity and 190 control individuals were included. The validation sample was 653 children from two birth cohorts belonging to the INMA (Infancia y Medio Ambiente [Environment and Childhood] )project. 109 SNPs located in the genes FTO, SEC16B, BDNF, ETV5, SH2B1, GNPDA2, LYPLAL1, MSRA, TFAP2, KCTD15, MTCH2 and NEGR1, previously reported in association to body mass index (BMI) were analysed. For the validation sample, association between genome-wide data and BMI measurements between 3.5 and 5 years of age, were evaluated. The GRS includes six SNPs in the genes FTO, TFAP2B, SEC16B, ETV5 and SH2B1. The score distribution differs among cases and controls (P = 9.2 × 10(-14) ) showing a significant linear association with obesity (odds ratio [OR] per allele = 1.69; confidence interval [CI] 95% = 1.46-1.97; P = 4.3 × 10(-1) and area under the receiver operating characteristic curve [AUC] = 0.727; CI 95% = 0.676-0.778). The results were validated by the INMA cohort (OR per allele = 1.23 CI 95% = 1.03-1.48 and AUC = 0.601 CI 95% = 0.522-0.680). The use of our proposed genetic score provides useful information to determine those children who are susceptible to obesity. To improve the efficiency of clinical prevention and treatment of obesity, it is essential to design individualized based protocols in advance knowledge of the molecular basis of inherited susceptibility. Show less