RISK OF LOW VIT D STATUS & FUNCTION: RACE, POPULATION ANCESTRY & SKIN REFLECTION

这个子项目是利用由NIH/NCRR资助的中心拨款提供的资源的许多研究子项目之一。子项目和调查员(PI)可能从另一个NIH来源获得了主要资金，因此可能会出现在其他CRISE条目中。列出的机构是针对中心的，而不一定是针对调查员的机构。研究表明，维生素D和维生素D反应基因在预防乳腺癌、结肠癌、前列腺癌和肾癌方面发挥了作用。有人提出，维生素D和维生素D受体等多态基因流行率的显著种族差异可能是非裔美国人癌症发病率较高的一些显著种族/民族差异的原因。然而，维生素D反应基因功能的种族/民族差异尚不清楚。此外，使用自我报告的种族来确定种族/民族差异可能与维生素D状态和维生素D反应基因的功能在生物学上相关，也可能不相关。我们建议使用三种不同的方法来研究血清维生素D和淋巴细胞中维生素D反应性的差异：自我报告的种族，通过基因祖先信息标记衡量的群体血统，以及通过皮肤反射率衡量的色素沉着。具体目的：1)确定血清维生素D和维生素D摄入量低的发生率(50名非洲裔美国人和50名白人)；2)估计研究志愿者淋巴细胞中维生素D反应基因的活性水平；以及3)通过自我报告的种族、群体血统和皮肤反射率分析维生素D状况(血清和饮食)和维生素D反应基因活动水平的差异，以便确定哪种衡量标准最能预测结果差异。这项研究的潜在好处包括推进癌症风险种族/民族差异的分子研究，以及开发可能在基于人群的研究中有用的分子表型分析。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Sudies suggest a role of vitamin D and vitamin D-responsive genes in the prevention of cancers of the breast, colon, prostate and kidney. It has been suggested that vitamin D and the significant racial variations in the prevalence of polymorphic genes such as the Vitamin D Receptor may account for some of the substantial racial/ethnic disparities in higher cancer incidence seen among African Americans. However, racial/ethnic differences in the function of vitamin D responsive genes are not known. Furthermore, the use of self-reported race in determining racial/ethnic disparities may or may not be biologically relevant to vitamin D status and the function of vitamin D-responsive genes. We propose to investigate the disparities in serum vitamin D and vitamin D responsiveness in the lymphocytes using three separate measures: self reported race, population ancestry as measured by gene ancestry informative markers, and pigmentation as measured by skin reflectance. Specific Aims: 1) Determine the prevalence of low serum vitamin D and vitamin D intake (50 African American and 50 white); 2) Estimate the activity level of vitamin D-responsive genes in the lymphocytes of study volunteers; and 3) Analyze differences in vitamin D status (serum and dietary) and the activity level of vitamin D responsive genes by self-reported race, population ancestry and skin reflectance in order to determine which measure best predicts outcome disparities. The potential benefits of this research include the advancement of molecular studies of racial/ethnic differences in cancer risk, and the development of a molecular phenotyping assay that might be useful in population-based studies.