In addition, a new mutation was found in exon 20 of the insulin receptor gene in a patient with moderate insulin resistance associated with morbid obesity, acanthosis nigricans, and polycystic ovary syndrome.
We used the polymerase chain reaction to amplify a region of the gene for the beta 3-adrenergic receptor encoding amino acid residues 27 to 110 in genomic DNA extracted from leukocytes from 185 patients with morbid obesity (body-mass index [the weight in kilograms divided by the square of the height in meters], > 40) and 94 normal subjects.
We have thus been able to confirm a tight relationship between serum leptin and body mass but have found no evidence for genetic linkage of the ob gene markers to morbid obesity in a population considered to represent a genetic isolate and to be an ideal model for studies of complex disorders.
These results suggest that NPY and NPY-Y1/ Y5 receptors are unlikely to be implicated in the development of human morbid obesity, at least in the French Caucasian population.
The massive obesity caused in rodents by the disruption of the leptin-receptor signal through genetic defects at the level of either leptin (OB) or leptin receptor (OB-R) has raised the question of the relevance of these genes to morbid obesity in humans.
The massive obesity caused in rodents by the disruption of the leptin-receptor signal through genetic defects at the level of either leptin (OB) or leptin receptor (OB-R) has raised the question of the relevance of these genes to morbid obesity in humans.
In rodents, homozygous mutations in genes encoding leptin or the leptin receptor cause early-onset morbid obesity, hyperphagia and reduced energy expenditure.
In rodents, homozygous mutations in genes encoding leptin or the leptin receptor cause early-onset morbid obesity, hyperphagia and reduced energy expenditure.
In addition to their early-onset morbid obesity, patients homozygous for this mutation have no pubertal development and their secretion of growth hormone and thyrotropin is reduced.
In humans, mutations in leptin, leptin receptor, prohormone convertase 1 (PC1), pro-opiomelanocortin (POMC), melanocortin 4-receptor (MC4-R), and peroxisome proliferator-activated receptor (PPAR) gamma2 genes have been described in patients with severe obesity.
We have previously demonstrated that genetically based leptin deficiency due to a missense leptin gene mutation in a highly consanguineous extended Turkish pedigree is associated with morbid obesity and hypogonadism.
In humans, mutations in leptin, leptin receptor, prohormone convertase 1 (PC1), pro-opiomelanocortin (POMC), melanocortin 4-receptor (MC4-R), and peroxisome proliferator-activated receptor (PPAR) gamma2 genes have been described in patients with severe obesity.
We hypothesize that haploinsufficiency of SIM1, possibly acting upstream or downstream of the melanocortin 4 receptor in the PVN, is responsible for severe obesity in our subject.
In order to examine the involvement of leptin in the ossification of spinal ligaments (OSL), the present study examined (i) serum levels of leptin and insulin in OSL patients and controls, (ii) serum leptin levels in children of OSL females with severe obesity, (iii) the expression of leptin receptor mRNA in human spinal ligaments, and (iv) effects of leptin on cultured human ligament cells.
In order to examine the involvement of leptin in the ossification of spinal ligaments (OSL), the present study examined (i) serum levels of leptin and insulin in OSL patients and controls, (ii) serum leptin levels in children of OSL females with severe obesity, (iii) the expression of leptin receptor mRNA in human spinal ligaments, and (iv) effects of leptin on cultured human ligament cells.
We hypothesize that haploinsufficiency of SIM1, possibly acting upstream or downstream of the melanocortin 4 receptor in the PVN, is responsible for severe obesity in our subject.