Melanocortin-4 receptor gene variants in Chilean families: association with childhood obesity and eating behavior.
OBJECTIVE
To screen for mutations in the coding region of the melanocortin-4 receptor (MC4R) gene and to assess the association between the rs17782313 variant near MC4R with childhood obesity and eating behavior.


METHODS
A cross-sectional sample of 221 obese Chilean children and 268 parents were incorporated in the study to assemble 134 case-parent trios. We performed direct sequencing of the MC4R coding region while the rs17782313 variant was genotyped by a Taqman assay. Eating behavior scores were calculated using the Child Eating Behavior and Three Factor Eating Questionnaires adapted for Chilean families.


RESULTS
A low frequency of genetic variation in the coding region of MC4R was found in Chilean obese children (Thr150Ile mutation and polymorphisms Ile251Leu and Val103Ile). The rs17782313 variant is possibly associated with satiety responsiveness (P = 0.01) and enjoyment of food scores (P = 0.03).


CONCLUSIONS
The rs17782313 variant may influence eating behavior in obese children.
Valladares
M
M
Department of Nutrition, Diabetes and Metabolism, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile.
Domínguez-Vásquez
P
P
Obregón
A M
AM
Weisstaub
G
G
Burrows
R
R
Maiz
A
A
Santos
J L
JL
D019943:Amino Acid Substitution; D000886:Anthropometry; D001066:Appetite; D002648:Child; D002652:Child Behavior; D002677:Chile; D003430:Cross-Sectional Studies; D004252:DNA Mutational Analysis; D005247:Feeding Behavior; D005260:Female; D056726:Genetic Association Studies; D006579:Heterozygote; D006801:Humans; D008297:Male; D009419:Nerve Tissue Proteins / Q000737:chemistry / Q000235:genetics*; D009765:Obesity / Q000097:blood / Q000235:genetics*; D016366:Open Reading Frames / Q000235:genetics; D010290:Parents; D011110:Polymorphism, Genetic; D020641:Polymorphism, Single Nucleotide; D044105:Receptor, Melanocortin, Type 4 / Q000737:chemistry / Q000235:genetics*; D012528:Satiety Response; D013223:Statistics as Topic; D011795:Surveys and Questionnaires
C470072:MC4R protein, human; D009419:Nerve Tissue Proteins; D044105:Receptor, Melanocortin, Type 4