Related Experiment Video
Updated: Jul 19, 2026

Experimental Approach to Examine Leptin Signaling in the Carotid Bodies and its Effects on Control of Breathing
Published on: October 25, 2019
Association analysis of genes involved in the leptin-signaling pathway with obesity in Brazil
V S Mattevi1, V M Zembrzuski, M H Hutz
1Genetics Department, Federal University of Rio Grande do Sul, Porto Alegre, Brazil.
Objective:
To investigate associations of polymorphisms in the LEP, LEPR and NPY genes with obesity-related traits in a Brazilian population of European descent.
Methods:
A total of 183 women and 153 men (mean body mass index (BMI), 26.1+/-4.8 kg/m(2)) were genotyped using the PCR-RFLP procedure for the LEP A19G, LEPR Gln223Arg, LEPR PRO1019pro and NPY Leu7Pro polymorphisms. Frequencies were compared among normal-weight and overweight plus obese groups with chi-square tests, mean BMI and waist circumference were compared among genotypes by t-tests and analysis of variance.
Results:
The genotype and allele frequencies of the LEPR Gln223Arg polymorphism were significantly different between normal-weight and overweight plus obese groups (P=0.013 and 0.009, respectively). Although there was no difference in the mean adjusted BMI among the three LEPRGln223Arg genotypes, a trend was observed for Arg/Arg individuals to have a higher mean BMI compared to Gln/Gln homozygotes, with heterozygote individuals presenting intermediate mean BMI between the two homozygote groups (ANOVA, P=0.063). However, in non-smokers, the LEPR Gln223Arg polymorphism showed a highly significant effect over BMI (P=0.009). When the analysis was restricted to premenopausal women, a highly significant effect of NPY was observed. Women bearing the Pro variant presented a lower BMI than wild-type homozygotes (P=0.001).
Conclusion:
Our findings suggest that genetic variability in the leptin receptor and neuropeptide Y genes is implicated in body weight regulation, the LEPR Gln223Arg variant being associated with a BMI increase in this Caucasian population, especially in non-smokers, while the NPY Leu7Pro polymorphism was associated with BMI reduction in premenopausal women.
More Related Videos
14:56Sample Preparation to Bioinformatics Analysis of DNA Methylation: Association Strategy for Obesity and Related Trait Studies
Published on: May 6, 2022
06:16White and Brown Adipose Grafts: An Approach to Correct Reproductive, Metabolic, and Renal Deficits in Black and Tan Brachyury (BTBR) Obese Mice
Published on: September 9, 2025
Related Concept Videos
Lethal Alleles
Lucien Cuénot discovered lethal alleles in 1905 while studying the inheritance of coat color in mice. The agouti gene is responsible for the color of the coat in mice. This gene codes for an agouti-signaling protein, which is responsible for melanin distribution in mammals. The wild-type allele gives rise to gray-brown coat color in mice, while the mutant allele gives rise to yellow coat color. In addition to coat color, the agouti gene is associated with the yellow...
Genome-wide Association Studies-GWAS
GWAS does not require the identification of the target gene involved in...
Regulation of Food Intake
Obesity
Pharmacokinetics in Obese Patients: Drug Absorption and Distribution
Pharmacokinetics in Obese Patients: Drug Metabolism and Excretion