DNA POLYMORPHISMS IN CLINICAL MEDICINE

在本提案中，我们将使用DNA多态性用于以下目的： 1)产生还原β-珠蛋白的不同突变的阐明 基因表达（β地中海贫血）在中国和美国黑人。 使用 地中海贫血基因突变研究的经验， 地中海人和亚洲印第安人，我们预计，新的和不同的 产生β-地中海贫血的突变将与每种不同的 中国人β-珠蛋白基因簇多态位点单倍型 美国黑人 所有导致表达减少的突变 迄今为止发现的β-珠蛋白基因在物理上位于β-珠蛋白中， 基因本身 我们希望在其他突变中找到一种完全正常的 β-珠蛋白基因与表达减少相关，提供了第一个 β-珠蛋白基因外的调节突变的证据。 我们也 希望找到“帽”位点的突变以及多聚腺苷酸化， β-珠蛋白基因的位点，这将提供重要信息， 对真核生物正常基因表达的理解。 2)家族性甲状旁腺功能减退症的分子基础研究 （FH）. 使用前甲状旁腺激素基因（ppPTH）和DNA的克隆， 在这个基因附近的多态性，我们将尝试i）发现 FH中的缺陷是否与ppPTH基因相关，以及ii） 表征产生降低表达的缺失和非缺失突变体 这个基因。 3)在来自大量无关个体的DNA样本中检测到 不同种族之间是否存在单核苷酸差异 来自膀胱癌细胞系EJ和T24的癌基因以及来自膀胱癌细胞系EJ和T24的癌基因。 正常人类同源物确实是与致癌性相关的罕见突变， 或与任何致癌作用无关的简单多态性。 的 在甘氨酸的密码子#12中大于T的突变G消除了 限制性内切核酸酶Nae I和Nsp I的切割位点， 因此在Southern印迹后是可检测的。 这个问题的答案 确定这种特定的突变是否可以用作“标记”， 膀胱癌患者家属的“危险因素” carcinoma.

In this proposal we will use DNA polymorphisms for the following purposes: 1) Elucidation of the different mutations producing reduce Beta-globin gene expression (Beta-thalassemia) in Chinese and American Blacks. Using the experience from the study of the Beta-thalassemia mutations in Mediterraneans and Asiatic Indians we anticipate that new and different mutations producing Beta-thalassemia will be associated with each different haplotype of polymorphic sites in the Beta-globin gene cluster in Chinese and American Blacks. All the mutations leading to reduced expression of the Beta-globin gene found so far are physically located in the Beta-globin gene itself. We hope to find among other mutations an entirely normal Beta-globin gene associated with reduced expression, providing the first evidence of a regulatory mutation outside of the Beta-globin gene. We also hope to find mutations of the "cap' site as well as the polyadenylation site of the Beta-globin gene which will provide important information for the understanding of the normal gene expression in eukaryotes. 2) Elucidation of the molecular basis of familial hypoparathyroidism (FH). Using clones of the preproparathyroid hormone gene (ppPTH) and DNA polymorphisms in the vicinity of this gene we will try to i) discover whether the defect in FH is associated with the ppPTH genes, and ii) characterize deletion and non-deletion mutants producing reduced expression of this gene. 3) Detect in DNA samples from a large number of unrelated individuals from different ethnic groups, whether the single nucleotide difference between the oncogene from the bladder carcinoma cell lines EJ and T24 and the normal human homologue is indeed a rare mutation related to oncogenicity, or a simple polymorphism not related to any oncogenic effects. The mutation G greater than T in the codon #12 for glycine eliminates a cleavage site for the restriction endonucleases Nae I and Nsp I and is therefore detectable after Southern blotting. The answer to this question determines whether this particular mutation can be used as a "marker" or "risk factor" for the families of individuals affected with bladder carcinoma.