Leptin and Leptin receptor polymorphisms, plasma Leptin levels and obesity in Tunisian volunteers

Abstract

Adipose tissue is an important endocrine organ that secretes a number of adipokines, like Leptin (LEP). The aim this study was to investigate the prevalence of single nucleotide polymorphisms in LEP gene (LEP 3'UTR A/C, -2548 G/A) and LEPR (K109R and Q223R) and their association with Leptin level and obesity. We recruited 169 non-obese (body mass index [BMI] = 24.51-3.69 kg/m ) and 160 obese (BMI = 36-4.78 kg/m ) patients. Genotyping was performed using polymerase chain reaction-restriction fragment length polymorphism, BMI was calculated, and Leptin level was measured by ELISA. Statistical analyses were performed by spss19.0. According to LEP 3'UTR A/C polymorphism, AC and CC genotype carriers had higher Leptin levels than AA genotype carriers, respectively, 31[0.05-148.8] (P = .008) vs 41[0.05-111.6] (P = .003). The K109R polymorphism was associated with obesity (P = .025) and seems to significantly decrease the LEP levels (P < .001). Concerning LEP G2548A polymorphism, our results showed that the OR of obesity associated with 2548 AA/GG was 1.87[1.106-2.78] P = .028 vs 1.41[1.035-1.85] P = .045 for 223AA/GG polymorphism. In our haplotype analysis, one haplotype seems to be the more protective and one other seems to be the highest risk to obesity. LEP 3'UTR A/C and LEPR K109R polymorphisms were associated with Leptin level and obesity.

Associations of leptin and leptin receptor genetic variants with coronary artery disease: a meta-analysis

“…Second, it is also possible that LEP/LEPR variants may be linked to each other or even linked to other unidentified genes, which could also impact individual susceptibility to CAD [26]. Second, it is worth noting that the functional significances of two investigated LEPR variants were also well established [27,28], yet no significant associations were observed for these two variants. Since the sample sizes of pooled analyses in the current meta-analysis were still relatively small, it is possible that our study was still not statistically adequate to detect the actual associations between LEP/LEPR variants and CAD in every genetic comparison.…”

Leptin and Obesity: Role and Clinical Implication

“…A single-nucleotide polymorphism identified in the 5’-untranslated region of the leptin gene (LEP -2548 G/A polymorphism) and its association with obesity is the most studied in humans. Still, the literature data are inconsistent ( 101 – 105 ). Carayol et al designed and performed the first protein quantitative trait locus (pQTL) analysis in obesity and examined the role of genetic variations in determining protein level variation ( 106 ).…”

Polimorfismos de los genes del sistema leptina-melanocortina asociados con la obesidad en la población adulta de Barranquilla

“…En este sentido, la frecuencia del alelo G en nuestra población fue predominante (45,2 %) en el grupo con peso normal (p>0,05), lo cual es similar a lo encontrado en poblaciones de Chile y México. Por su parte, el genotipo AA se asoció significativamente con la obesidad en voluntarios de Túnez (OR=1,41; IC95% 1,035-1,85) (p=0,045) 24 .…”