RAPID ISOLATION OF DIET-RESPONSIVE OBESITY GENES

饮食诱导的肥胖(DIO)与糖尿病发病率的增加有关 动脉粥样硬化、糖尿病和高血压。在鉴定基因的同时 任何复杂的疾病对人类来说都是困难的，这些问题将 DIO的风险增加，很难区分导致DIO的基因 自发性肥胖来自那些引起DIO的人。相比之下，这些工具 可用于分析小鼠的复杂疾病，结合 相对容易控制饮食，表明认同感和 用小鼠模型分离引起DIO的基因将是可能的。 这个项目的长期目标是分离和鉴定基因。 导致酒后驾车。这项提议的特点是它使用了现有的 同种小鼠品系可实现DIO的快速检测和分离 基因。同基因小鼠品系是由近亲交配的小鼠品系通过 杂交和选择的方法它们与背景完全相同 紧张，除了一个小的 来自供体菌株的染色体区域。现有资源的利用 同源菌株作为一种快速定位克隆的方法是通用的和 对寻找与其他复合体有关的新基因的影响 疾病可能会很严重。 第一个目标是检查DIO下的基因分离 同源品系与背景品系杂交F2。我们已经确认了五个 表现出显著不同体脂的同种小鼠品系 百分比或肥胖指数(脂肪垫重量总和除以屠体 体重)比它们的背景菌株都被放在高脂肪上时， 高蔗糖饮食。这些菌株中的每一种都将进行适应性测试，因为 通过检测100只F2小鼠获得定位克隆资源 同源菌株和背景菌株的杂交。两个人的身份 分离群，对应于同源株和背景株 基因分型，将通过检查个别表型或 表型组合。 第二个目标是启动对潜在基因的定位克隆 饮食导致的肥胖。一个包含新的肥胖症基因和 这表明肥胖特征被最明显地分为两部分 群体将扩大到包括1000只F2小鼠。这些老鼠将被分型 用于该基因座附近的所有可用的PCR标记。当我们识别标记时 在DIO基因的1厘米范围内，我们将分离出连锁的 基因组克隆(YAC、BAC、P1或PAC克隆)。将构建一个重叠群 这包括DIO基因。

Diet-induced obesity (DIO) is associated with increased incidences of atherosclerosis, diabetes, and hypertension. While identification of genes underlying any complex disease is difficult in humans, these problems will be increased for DIO, where it will be hard to distinguish genes that cause spontaneous obesity from those that cause DIO. In contrast, the tools available for analysis of complex disease in mice, combined with the relative ease of controlling diets, suggest that identification and isolation of genes causing DIO will be possible with mouse models. The long range goal of this project is to isolate and identify genes causing DIO. This proposal is distinguished by its use of existing congenic mouse strains to enable rapid detection and isolation of DIO genes. Congenic mouse strains are derived from inbred mouse strains by a regimen of crossing and selection They are identical to a background strain except for a small chromosomal region derived from a donor strain. The use of existing congenic strains as a rapid approach to positional cloning is generic and the impact on the search for novel genes contributing to other complex diseases could be great. The first objective is to examine the segregation of genes underling DIO in F2 crosses of congenic and background strains. We have identified five strains of congenic mice that exhibit significantly different body lipid percent or adiposity index (sum of fat pad weights divided by carcass weight) than their background strains when both are placed on a high-fat, high-sucrose diet. Each of these strains will be tested for suitability as a resource for positional cloning by examining 100 F2 mice derived from crosses of the congenic and background strains. Identification of two segregating groups, corresponding to congenic and background strain genotypes, will be made by examination of individual phenotypes or combinations of phenotypes. The second objective is to initiate positional cloning of genes underlying diet-induced obesity. The one cross that includes a novel obesity gene and that exhibits the most distinct segregation of obesity traits into two groups will be expanded to include 1000 F2 mice. These mice will be typed for all available PCR markers near the locus. When we identify markers within 1 cM of the gene underlying DIO, then we will isolate linked genomic clones (YAC, BAC, P1 or PAC clones). A contig will be constructed that includes the DIO gene.