Evaluation of association of DRD2 TaqIA and -141C InsDel polymorphisms with food intake and anthropometric data in children at the first stages of development

Abstract The reward sensation after food intake may be different between individuals and variants in genes related to the dopaminergic system may indicate a different response in people exposed to the same environmental factors. This study investigated the association of TaqIA (rs1800497) and -141C InsDel (rs1799732) variants in DRD2/ANKK1 gene with food intake and adiposity parameters in a cohort of children. The sample consisted of 270 children followed until 7 to 8 years old. DNA was extracted from blood and polymorphisms were detected by PCR-RFLP analysis. Food intake and nutritional status were compared among individuals with different SNP genotypes. Children carrying the A1 allele (TaqIA) had higher energy of lipid dense foods (LDF) when compared with A2/A2 homozygous children at 7 to 8 years old (GLM p=0.004; Mann Whitney p=0.005). No association was detected with -141C Ins/Del polymorphism. To our knowledge, this is the first association study of the DRD2 TaqIA and -141C Ins/Del polymorphism with food intake and anthropometric parameters in children. DRD2 TaqIA polymorphism has been associated with a reduction in D2 dopamine receptor availability. Therefore, the differences observed in LDF intake in our sample may occur as an effort to compensate the hypodopaminergic functioning.

摘要 个体进食后的奖赏感知存在个体差异，而多巴胺能系统相关基因的变异，或可提示暴露于相同环境因素的人群存在不同的应答反应。本研究针对儿童队列，探究了DRD2/ANKK1基因中TaqIA（rs1800497）与-141C InsDel（rs1799732）变异与进食行为及体脂参数的关联。本研究共纳入270名儿童，对其随访至7至8岁阶段。通过血液样本提取基因组DNA，并采用聚合酶链反应-限制性片段长度多态性（PCR-RFLP）技术检测基因多态性。对携带不同单核苷酸多态性（SNP）基因型的儿童的进食行为与营养状况进行了组间比较。在7至8岁时，携带A1等位基因（TaqIA）的儿童，其高脂密度食物（LDF）的能量摄入显著高于A2/A2纯合子儿童（广义线性模型GLM：p=0.004；曼-惠特尼U检验Mann Whitney：p=0.005）。未发现-141C Ins/Del多态性与进食行为或体脂参数存在显著关联。据我们所知，本研究是首个针对儿童群体，探究DRD2 TaqIA与-141C Ins/Del多态性与进食行为及人体测量学参数关联的研究。已有研究证实，DRD2 TaqIA多态性会导致多巴胺D2受体的可用性降低。因此，本研究样本中观察到的LDF摄入差异，可能是机体为代偿多巴胺能功能低下所做出的适应性调节。