Association of UCP3 gene -55C>T polymorphism and obesity in a Spanish population.
OBJECTIVE
The uncoupling protein 3 (UCP3) gene has been suggested as a possible determinant affecting obesity risk given its function in the regulation of energy metabolism. However, available genetic association studies have been inconsistent, which could be attributable to not considering individual lifestyle patterns, such as physical activity, a factor that affects UCP3 expression. The objective of this study was to assess the association between the UCP3 -55C>T polymorphism and the risk of obesity.


METHODS
Case-control study conducted in a sample of Spanish adults. 157 obese subjects (BMI > or = 30) and 150 controls (BMI < 25) participated in the study. UCP3 -55C>T polymorphism was identified by the polymerase chain reaction-restriction fragment length polymorphism methodology.


RESULTS
The odds ratio (OR) for obesity (95% confidence interval [CI]) according to the presence of UCP 3 gene -55C>T polymorphism (heterozygotes and homozygotes merged together), adjusting for age, sex, and recreational physical activity, was 0.61 (0.37-1.00), p = 0.05. Interestingly, this association was only manifest among those with higher recreational physical activity (OR: 0.46, 95% CI 0.21-0.99, p = 0.05) and not among those with lower physical activity (OR: 0.84, 95% CI 0.41-1.70, p = 0.84).


CONCLUSIONS
UCP3 -55C>T polymorphism carriers have apparently a lower risk of obesity when taking into consideration recreational energy expenditure. Interestingly, this inverse beneficial association may only occur in people with a high level of physical activity.
Alonso
Alvaro
A
Department of Preventive Medicine and Public Health, University of Navarra, Pamplona, Spain.
Martí
Amelia
A
Corbalán
María Soledad
MS
Martínez-González
Miguel A
MA
Forga
Luis
L
Martínez
J Alfredo
JA
D000328:Adult; D015992:Body Mass Index; D002352:Carrier Proteins / Q000235:genetics*; D016022:Case-Control Studies; D016001:Confidence Intervals; D015444:Exercise / Q000502:physiology*; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D007473:Ion Channels; D008297:Male; D024101:Mitochondrial Proteins; D009765:Obesity / Q000453:epidemiology* / Q000235:genetics*; D016017:Odds Ratio; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D013030:Spain / Q000453:epidemiology; D014475:Uncoupling Agents; D000071247:Uncoupling Protein 3
D002352:Carrier Proteins; D007473:Ion Channels; D024101:Mitochondrial Proteins; C000604392:UCP3 protein, human; D014475:Uncoupling Agents; D000071247:Uncoupling Protein 3