Association of the melanocortin-4 receptor V103I polymorphism with dietary intake in severely obese persons.
BACKGROUND
Several studies have reported that carriers of the 103I allele of the melanocortin-4 receptor (MC4R) gene had lower body weight than did persons with the wild-type genotype. A recent study found an association of the MC4R 103I variant with carbohydrate intake, which may mediate some of the association of this variant with leanness.


OBJECTIVE
The purpose of the study was to investigate the association between the MC4R V103I polymorphism and the dietary intake of persons with severe obesity, which was derived by using the Willett food-frequency questionnaire.


METHODS
The MC4R V103I polymorphism was genotyped in a group of 1029 severely obese white subjects with an average body mass index (BMI; in kg/m(2)) of 46.0 (range: 33-92).


RESULTS
Carriers of the 103I allele had significantly higher daily energy (364 kcal/d or 19%; P = 0.03) and carbohydrate (57 g/d or 27%; P = 0.01) intakes than did noncarriers, but there was no relation with BMI. No notable association of this polymorphism with lipid and glucose variables of the metabolic syndrome was observed.


CONCLUSIONS
The higher dietary intake of carbohydrates in severely obese persons with the MC4R 103I variant is in line with previous findings. It may indicate a differential effect on body size measures in extremely obese subjects as compared with the general population.
Pichler
Michaela
M
Division of Genetic Epidemiology, Department of Medical Genetics, Molecular and Clinical Pharmacology, Innsbruck Medical University, Innsbruck, Austria.
Kollerits
Barbara
B
Heid
Iris M
IM
Hunt
Steven C
SC
Adams
Ted D
TD
Hopkins
Paul N
PN
Kronenberg
Florian
F
D000328:Adult; D019943:Amino Acid Substitution; D001823:Body Composition; D015992:Body Mass Index; D004040:Dietary Carbohydrates; D002149:Energy Intake; D005260:Female; D014644:Genetic Variation; D006801:Humans; D008055:Lipids / Q000097:blood; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000235:genetics* / Q000503:physiopathology*; D011110:Polymorphism, Genetic; D020641:Polymorphism, Single Nucleotide; D044105:Receptor, Melanocortin, Type 4 / Q000235:genetics*
D004040:Dietary Carbohydrates; D008055:Lipids; D044105:Receptor, Melanocortin, Type 4
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