RESUMEN
BACKGROUND: food is a powerful reinforcer that motivates people to eat. The TaqI A1 polymorphism (rs1800497; T>C) downstream of the dopamine D2 receptor (DRD2) gene has been associated with diminished DRD2 receptor density, higher food reinforcement, and impaired eating behavior in adults. OBJECTIVE: to evaluate the association between the rs1800497 polymorphism and the reinforcing value of food and eating in the absence of hunger in Chilean children. MATERIAL AND METHOD: nineteen Chilean children (aged 8-12 years) who were carriers of the A1-allele and 19 age- and gender-matched non-carriers (A2-allele) were evaluated on the reinforcing value of food and eating in the absence of hunger. Anthropometric measures were performed by standard procedures. Briefly, children received a standard pre-load lunch followed by an ad-libitum exposure to palatable foods. RESULTS: no differences were found between A1-allele carriers and non-carriers, whether obese or non-obese, in ad libitum energy intake, macronutrient consumption, or the relative reinforcing value of food (p > 0.05). In obese children, A1 carriers reported significantly lower satiety and fullness before lunch (p < 0.05). However, in children with normal weight A1 carriers were found to exhibit trends for greater satiety and fullness before lunch when compared to non-carriers, but this trend reversed after lunch such that carriers exhibited lower satiety and fullness (p = 0.06). CONCLUSIONS: although TaqI A1 may play an important role in some eating behavior-related traits such as satiety and fullness, especially in obese children, our findings indicate that this polymorphism does not appear to affect eating in the absence of hunger or food reinforcement in children
ANTECEDENTES: los alimentos son un poderoso reforzador de la alimentación. El polimorfismo TaqI A1 (rs1800497; T> C) del gen del receptor 2 de dopamina (DRD2) se ha asociado con una menor densidad de DRD2, un mayor refuerzo alimentario y un comportamiento alimentario alterado en adultos. OBJETIVO: evaluar la asociación entre el polimorfismo rs1800497, el valor reforzador del alimento y la conducta de comer en ausencia de hambre en niños chilenos. MATERIAL Y MÉTODO: treinta y ocho niños chilenos, 19 portadores del alelo A1 y 19 no portadores (alelo A2), pareados por género y edad, fueron evaluados en condiciones de laboratorio para determinar el valor reforzador del alimento y la conducta de comer en ausencia de hambre. Las mediciones antropométricas se realizaron por procedimientos estándar. Brevemente, los niños recibieron un almuerzo estándar seguido de una exposición ad-libitum a alimentos sabrosos. RESULTADOS: no hubo diferencias en la ingesta ad libitum de energía, ni en el consumo de macronutrientes, ni en el valor reforzador del alimento entre los portadores del alelo A1 frente a los no portadores (p > 0,05). Entre los niños obesos, los portadores del alelo A1 reportaron un menor nivel de saciedad y plenitud pre-almuerzo (p < 0,05). Sin embargo, entre los niños con normopeso se observó que los portadores de A1 tenían tendencia a presentar un mayor grado de saciedad y plenitud (pre-almuerzo) frente a los no portadores. Esta tendencia se invirtió post-almuerzo, de modo que los portadores exhibieron menor saciedad y plenitud (p = 0,06). CONCLUSIONES: la variante TaqI A1 podría desempeñar un papel importante en algunos rasgos relacionados con la conducta alimentaria, como la saciedad y la plenitud
Asunto(s)
Humanos , Masculino , Femenino , Niño , Hambre/fisiología , Variación Genética/genética , Conducta Alimentaria/fisiología , Ingestión de Energía/genética , Obesidad/genética , Receptores de Dopamina D2/genética , Chile , Variación Genética/efectos de los fármacos , Polimorfismo Genético/genética , Antropometría , Peso Corporal/genética , Ingestión de Energía/fisiología , Receptores de Dopamina D2/fisiologíaRESUMEN
OBJECTIVES: The aim of this study was to assess the association between the single-nucleotide polymorphism rs9939609 in the FTO gene and homeostatic/non-homeostatic eating behavior patterns in Chilean children. METHODS: A cross-sectional study was conducted in 258 children (44% female; 8-14 y of age). Anthropometric measurements (weight, height, Z-score of height, body mass index, and waist circumference) were performed. Eating behavior was assessed using the Eating in Absence of Hunger Questionnaire; the Child Eating Behavior Questionnaire; the Three Factor Eating Questionnaire, and the Food Reinforcement Value Questionnaire. Genotype of rs9939609 was determined by a Taqman assay. Association of rs9939609 with eating behavior was assessed using non-parametric tests. RESULTS: Allelic frequencies of rs9939609 were estimated as 77% for the A allele and 23% for the T allele. We found that normal-weight girl A carriers had higher scores of Satiety Responsiveness and Slowness on the Eating subscale. Normal-weight boy A carriers showed significantly higher scores on the Negative Affect and lower scores of the Desire to Drink subscale. In overweight children, A carriers showed higher scores on the Food Responsiveness, Emotional Overeating, Enjoyment of Food, and Food Choice subscales and lower scores on the Satiety- Responsiveness and Slowness in Eating subscales. In obese children, we found higher scores on the Cognitive Restrained subscale and lower Food Choice. CONCLUSION: The rs9939609 A allele of the FTO gene is associated with eating behavior traits and may predispose to obesity.