肥胖已成为21世纪全球性的公共卫生问题。已有研究证实，在肥胖的少年儿童中，MS的比率极高。近年来研究发现，Ghrelin与物质和能量代谢平衡有密切关系，因此推测Ghrelin可能是一个与肥胖有关的基因。但就Ghrelin基因多态性是否与肥胖症有关尚存在争议。有研究表明Ghrelin基因编码区的变异与肥胖和2型糖尿病却未发现相关性。本研究选择宁夏回汉族6~18岁儿童青少年作为研究对象，选择回汉族肥胖合并MS、单纯肥胖及体质指数正常儿童青少年，通过病例对照研究，进行外周血白细胞基因组DNA的抽提，通过Ghrelin基因Leu72Met位点多态性分析，了解该基因位点变异在两民族不同群体儿童青少年间是否存在差异，进一步明确Ghrelin基因在回汉族儿童青少年肥胖和MS中的作用。探讨儿童肥胖和MS发生机制，为制定有效控制儿童肥胖和MS措施提供科学依据。

Obesity has become a 21 century global public health problem. Studies have confirmed that in obese children, MS ratio is extremely high. In recent years, the study found Ghrelin and material and energy metabolization balance has close relationship.therefore, We assume that Ghrelin may be a associated genes with obesity. But there is a dispute about Ghrelin genetic polymorphism and obesity relevant . Research has shown that the genetic encoding Ghrelin variation and obesity and type 2 diabetes but did not find correlation. This study selection HuiHan nationalities 6 to 18 years old in ningxia children as the research object, the choice HuiHan nationalities with obesity and MS, simple obesity and body mass index normal children, through the case control studies, in peripheral blood of white blood cells genomic DNA extraction, through the Ghrelin gene polymorphism Leu72Met site analysis, understand the gene loci in two different ethnic groups variation between children and youth are different, make clear further Ghrelin gene in HuiHan nationalities children obesity and MS in the role. Explore childhood obesity and MS happening mechanism, to make the control childhood obesity and MS measures to provide the scientific basis.