GENETICS OF BONE LOSS AND BONE STRENGTH IN WOMEN & MEN

女性骨质流失和骨质强度的遗传学

• 批准号: 7020553
• 负责人: MUNRO PEACOCK
• 金额: $ 45.5万
• 依托单位: INDIANA UNIV-PURDUE UNIV AT INDIANAPOLIS
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-07-01 至 2010-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7020553
• 关键词: African American; aging; biomechanics; bone density; caucasian American; computed axial tomography; developmental genetics; family genetics; gender difference; gene expression; genetic mapping; genetic polymorphism; genetic screening; genetic susceptibility; human subject; longitudinal human study; osteoporosis; patient oriented research; phenotype; quantitative trait loci; racial /ethnic difference; siblings

We have shown that QTL for both bone mineral density (BMD) and structure appear to be sex-specific. These potentially important findings will be corroborated by enlarging the current sample size of brothers from 700 to 1,000 pairs and comparing these with data we have collected in 1,225 sister pairs. Bone size is an important factor in determining bone strength and hence fracture risk. We have shown that there is a significant increase in the rate of bone expansion at the femoral neck that it is heritable, and that linkage analysis has identified a number of QTL. No comparable data have been collected in men. We will perform a 5 year longitudinal study in brother pairs to establish if there are sex-specific genes for expansion of bone size. Quantitative computerized tomography (CT) at the proximal femur provides volumetric BMD of cortical and trabecular bone, structural phenotypes, and mechanical phenotypes related to in vivo bone strength. We have found significant differences between white and black men in cortical BMD. In women, we have found QTL for cortical and trabecular volumetric BMD at femoral neck. To corroborate these key findings we propose to increase our sample size by 300 pairs of brothers and 300 pairs of sisters for CT phenotypes. Achievement of these specific aims will provide fundamental information on the presence of sex-specific genes underlying the normal variation in bone density, bone structure, and in vivo biomechanical phenotypes, all key components of bone strength and risk of fracture. Further, it will provide information on the genes underlying differences in bone strength between American whites and blacks. It is expected that these proposed studies will greatly contribute to our understanding for the reasons for the higher risk of osteoporotic fracture in women than men and in American whites than blacks. Importantly the genes responsible for these differences are likely to provide targets for novel and more specific therapy aimed at prevention and treatment of osteoporotic fracture.

我们已经证明骨矿物质密度 (BMD) 和结构的 QTL 似乎具有性别特异性。这些潜在的重要发现将通过将目前的兄弟样本量从 700 对扩大到 1,000 对并将其与我们在 1,225 对姐妹中收集的数据进行比较来得到证实。骨大小是决定骨强度和骨折风险的重要因素。我们已经证明，股骨颈骨扩张率的显着增加是可遗传的，并且连锁分析已经鉴定了许多QTL。尚未收集男性的可比较数据。我们将对兄弟进行一项为期 5 年的纵向研究，以确定是否存在导致骨骼尺寸扩张的性别特异性基因。股骨近端的定量计算机断层扫描 (CT) 提供皮质骨和小梁骨的体积 BMD、结构表型以及与体内骨强度相关的机械表型。我们发现白人和黑人的皮质骨密度存在显着差异。在女性中，我们发现了股骨颈皮质和小梁体积 BMD 的 QTL。为了证实这些关键发现，我们建议将 CT 表型的样本量增加 300 对兄弟和 300 对姐妹。这些具体目标的实现将提供有关骨密度、骨结构和体内生物力学表型正常变化背后的性别特异性基因存在的基本信息，这些基因是骨强度和骨折风险的所有关键组成部分。此外，它将提供以下信息： 美国白人和黑人之间骨骼强度差异的基因。预计这些拟议的研究将极大地有助于我们理解女性骨质疏松性骨折风险高于男性、美国白人高于黑人的原因。重要的是，造成这些差异的基因可能为旨在预防和治疗骨质疏松性骨折的新颖且更具体的疗法提供靶标。