Genetic Analysis of Hip Fragility

髋部脆弱的遗传分析

• 批准号: 7714823
• 负责人: CHARLES H TURNER
• 金额: $ 38.5万
• 依托单位: INDIANA UNIV-PURDUE UNIV AT INDIANAPOLIS
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-04-04 至 2011-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7714823
• 关键词: Affect; Alleles; Behavioral; Biology; Bone Diseases; Candidate Disease Gene; Cell Culture Techniques; Cellular biology; Chromosome Mapping; Chromosomes; Chromosomes, Human, Pair 1; Chromosomes, Human, Pair 4; Complex; Cost Measures; DNA Sequence; Europe; Evaluation; Exons; Gene Expression; Gene Expression Profiling; Gene Expression Regulation; Genes; Genetic; Genetic Recombination; Genetic Techniques; Genome; Genomics; Genotype; Goals; Hip region structure; Histology; Housing; Human; Inbred Strains Rats; Individual; Information Networks; Laboratory Rat; Literature; Location; Maps; Measurement; Measures; Metabolic; Modeling; Mus; Neck; Osteoblasts; Osteoclasts; Osteoporosis; Phenotype; Population; Proteins; Quantitative Trait Loci; RNA Interference; RNA Splicing; Rattus; Reporting; Research; Single Nucleotide Polymorphism; Site; Structure; Transcript; Variant; Work; base; bone; bone cell; congenic; cost; genetic analysis; genetic linkage analysis; genetic variant; genome wide association study; genome-wide; hemodynamics; in vivo; progenitor; public health relevance; research study; skeletal; trait; Affect; Alleles; Behavioral; Biology; Bone Diseases; Candidate Disease Gene; Cell Culture Techniques; Cellular biology; Chromosome Mapping; Chromosomes; Chromosomes, Human, Pair 1; Chromosomes, Human, Pair 4; Complex; Cost Measures; DNA Sequence; Europe; Evaluation; Exons; Gene Expression; Gene Expression Profiling; Gene Expression Regulation; Genes; Genetic; Genetic Recombination; Genetic Techniques; Genome; Genomics; Genotype; Goals; Hip region structure; Histology; Housing; Human; Inbred Strains Rats; Individual; Information Networks; Laboratory Rat; Literature; Location; Maps; Measurement; Measures; Metabolic; Modeling; Mus; Neck; Osteoblasts; Osteoclasts; Osteoporosis; Phenotype; Population; Proteins; Quantitative Trait Loci; RNA Interference; RNA Splicing; Rattus; Reporting; Research; Single Nucleotide Polymorphism; Site; Structure; Transcript; Variant; Work; base; bone; bone cell; congenic; cost; genetic analysis; genetic linkage analysis; genetic variant; genome wide association study; genome-wide; hemodynamics; in vivo; progenitor; public health relevance; research study; skeletal; trait

DESCRIPTION (provided by applicant): In 2001, our group began studies to determine the genetics causes of bone fragility. We chose to study rats, rather than mice, because the laboratory rat has proven to be an excellent model for human bone disorders, like osteoporosis. Because rats are larger than mice, it is easier to measure bone structure and strength at the femoral neck, which is a skeletal site of primary focus. Our first study involved a cross between Fischer 344 (F344) and Lewis (LEW) rats. Our second study focusing on Copenhagen 2331 (COP) and Dark Agouti (DA) rats began in 2003 and is the subject of this competitive renewal application. We have successfully mapped quantitative trait loci (QTLs) for femoral neck and femoral midshaft phenotypes, the primary and secondary goals of the project. Our work in the past five years has provided a clear direction for our proposed research in the next five years: we will identify genes within QTLs that affect bone biology. This project has three Aims. First, we will identify causative genes within our two QTLs with largest effect size: Chromosome (Chr) 4 for F344 and LEW rats (13% effect) and Chr 1 for COP and DA rats (14% effect). We plan to generate congenic rat models and conduct gene expression profiling followed by functional studies in vivo and using cultured osteoblasts and osteoclasts to identify genes that directly affect bone biology. Second, we will work with a large, world-wide research consortium to conduct a genome wide association study (GWAS) in heterogeneous stock (HS) rats. The GWAS led by Jonathan Flint will provide phenotypes and genotypes for over 2000 rats. Phenotypes will include: behavioral, metabolic, hematological, hemodynamic, immunological and skeletal (our contribution). Each rat will be genotyped for about 20,000 single nucleotide polymorphisms (SNPs). The results will allow us to identify new QTLs that affect bone traits and to reduce the number of candidate genes at each QTL from several dozen to a mere handful. Finally, we will identify gene expression QTLs (eQTLs) using a genome screen to map transcript abundance in 2nd filial (F2) rats derived from COP and DA progenitors. Variations in expression of individual genes will be mapped to locations on the genome to produce eQTLs. eQTL mapping allows one to identify cis-eQTLs for which expression levels can be correlated with a chosen bone phenotype to identify and prioritize genes most likely to alter bone biology. Also, we will identify trans- genes controlled by a given QTL and with this information we will construct networks of genes that underlie complex bone traits. Another unique feature of eQTL mapping is its ability to identify allele-specific regulation of gene expression on a genome-wide scale. Completion of these Aims will accelerate our progress toward identifying genes that affect bone fragility. PUBLIC HEALTH RELEVANCE: Our study will identify genes that cause bone fragility. We will use several inbred strains of rats in our experiments and apply modern genetics techniques like gene expression microarrays and single nucleotide polymorphism genotyping. Our goal is to find genetic causes for bone weakening conditions like osteoporosis so better treatments can be developed.

描述（由申请人提供）：2001年，我们的小组开始研究以确定骨骼脆弱性的遗传学原因。我们选择研究大鼠而不是小鼠，因为实验室大鼠已被证明是人类骨骼疾病的绝佳模型，例如骨质疏松症。因为大鼠比小鼠大，所以在股骨颈部测量骨骼结构和强度更容易，这是主要聚焦的骨骼部位。我们的第一个研究涉及Fischer 344（F344）和刘易斯（Lew）大鼠之间的交叉。我们的第二项研究重点是哥本哈根2331（COP）和Dark Agouti（DA）大鼠于2003年开始，是这种竞争更新应用的主题。我们已经成功映射了用于股骨颈和股骨中层表型的定量性状基因座（QTL），该表型是该项目的主要目标和次要目标。在过去五年中，我们在未来五年内为我们提出的研究提供了明确的方向：我们将在QTL中确定影响骨骼生物学的基因。该项目有三个目标。首先，我们将在两个QTL中确定效果最大的QTL中的因果基因：F344的染色体（CHR）4和LEW大鼠（13％效应）和COP和DA大鼠的ChR 1（14％效应）。我们计划生成先天大鼠模型并进行基因表达分析，然后在体内进行功能研究，并使用培养的成骨细胞和破骨细胞来鉴定直接影响骨骼生物学的基因。其次，我们将与一个全球范围内的大型研究联盟合作，以进行基因组广泛的关联研究（GWAS），以异质股（HS）大鼠进行。由乔纳森·弗林特（Jonathan Flint）领导的GWAS将为2000多只大鼠提供表型和基因型。表型将包括：行为，代谢，血液学，血液动力学，免疫学和骨骼（我们的贡献）。每只大鼠将用于约20,000个单核苷酸多态性（SNP）的基因分型。结果将使我们能够鉴定影响骨骼特征的新QTL，并将每个QTL的候选基因数量从几十个降低到少数。最后，我们将使用基因组筛选鉴定基因表达QTL（EQTL），以绘制源自COP和DA祖细胞的第二份归档（F2）大鼠中的转录物丰度。单个基因表达的变化将映射到基因组上的位置以产生EQTL。 EQTL映射允许人们识别可以与所选的骨表型相关的表达水平的顺式EQTL，以识别和优先级，并确定最有可能改变骨骼生物学的基因。此外，我们将确定由给定QTL控制的转移基因，并使用此信息，我们将构建基因网络，这些基因网络是基于复杂骨特征的基因。 EQTL映射的另一个独特特征是它在全基因组范围内识别基因表达的等位基因特异性调节的能力。这些目标的完成将加速我们在识别影响骨骼脆弱的基因方面的进步。公共卫生相关性：我们的研究将确定引起骨骼脆弱性的基因。我们将在实验中使用几种近交菌株，并应用现代遗传学技术，例如基因表达微阵列和单核苷酸多态性基因分型。我们的目标是为骨质疏松症（例如骨质疏松症）找到骨质衰弱的遗传原因，以便可以发展出更好的治疗方法。