ADPKD: Disease Spectrum & Genotype-Phenotype Correlations

ADPKD：疾病谱

• 批准号: 10220948
• 负责人: Peter C. Harris
• 金额: $ 51.03万
• 依托单位: MAYO CLINIC ROCHESTER
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-08-01 至 2023-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10220948
• 关键词: Alleles; Animal Model; Animals; Autosomal Dominant Polycystic Kidney; Biochemical; Biogenesis; Biological; Budgets; Cell surface; Cells; Cellular Assay; Clinical; Collaborations; Complex; Cyst; Cystic kidney; Data; Defect; Development; Diagnostic; Disease; End stage renal failure; Environment; Etiology; Event; Family; Fostering; Functional Imaging; Funding; Genes; Genetic; Genetic Diseases; Genetic Heterogeneity; Genotype; Germ-Line Mutation; Goals; Grouping; Hepatic; Hepatic Cyst; Image; Individual; Kidney; Knowledge; Machine Learning; Methodology; Methods; Modeling; Molecular Chaperones; Mosaicism; Mutation; Nonsense Mutation; Other Genetics; PRKCSH protein; Pathogenesis; Pathogenicity; Patient Selection; Patients; Penetrance; Pharmaceutical Preparations; Phenotype; Population; Process; Proprotein Convertase 1; Proprotein Convertase 2; Proteins; Renal function; Role; Scheme; Severities; Severity of illness; Signal Transduction; Testing; Therapeutic; Variant; base; disease phenotype; dosage; early onset; exome sequencing; human old age (65+); improved; in silico; in utero; in vitro Assay; in vivo; individual patient; individualized medicine; insight; large datasets; loss of function; molecular diagnostics; mouse model; mutant; mutation screening; next generation sequencing; novel; polycystic liver disease; prediction algorithm; prognostic; prognostic tool; protein folding; screening; therapy development; trafficking; variant of unknown significance

Autosomal dominant polycystic kidney disease (ADPKD) is a common monoallelic disorder associated with progressive cyst development and resulting in end stage renal failure (ESRD) in 50% of patients by 60y. However, there is considerable phenotypic variability, extending from in utero onset to patients with adequate renal function into old age. Autosomal dominant polycystic liver disease (ADPLD), as traditionally defined, results in PLD with minimal renal cysts. Classically there have been considered two ADPKD genes, PKD1 and PKD2, encoding PC1 and PC2, and two ADPLD genes, PRKCSH and SEC63, but in the past few years greater genetic heterogeneity has been described, with nine genes now implicated overall. Recent data also indicates an overlap in etiology and pathogenesis associated with ADPKD and ADPLD, with the efficient biogenesis and localization of the PC-complex central to both disorders. During the last funding period we identified a novel gene, GANAB, which is associated with both disorders, where the encoded protein, GII is involved in the maturation and trafficking of PC1. In this proposal we will take advantage of advances in next generation sequencing (NGS) methodologies, and large populations of ADPKD and ADPLD patients that have been assembled and screened for the classic genes, to hunt for novel genes for these disorders (Aim 1). The phenotype associated with these genes will be characterized (Aim 3) along with their mechanism of action (Aim 2). NGS methods will be perfected to screen the segmentally duplicated locus, PKD1, and to identify missed mutations at the known loci, including those present in just some cells due to mosaicism (Aim 1). The significance of many PKD1 nontruncating variants has been difficult to evaluate (classed as variants of unknown significance; VUS), but recently evidence that some are incompletely penetrant alleles partially explains phenotypic variability in PKD1 populations. In Aim 2 improved in silico predictions, in combination with machine learning, will improve the understanding of the pathogenicity and penetrance of VUS. A cellular assay of the biogenesis and trafficking of this PC-complex will also be employed to quantify the penetrance of VUS. The mechanism of pathogenesis will be explored in animal models with ultralow penetrant (ULP) Pkd1 or Pkd2 alleles. Employing the large clinically, imaging, and genetically well-defined populations phenotypic groupings of patients will be defined that will then be compared to the genic and PKD1 allelic groups (Aim 3). This iterative process will allow the Variant Score (VS) associated with each PKD1 VUS to be refined. In a separate population the revised VS, alone and in combination with clinical, functional, and imaging data, will be employed to generate a comprehensive, predictive algorithm for ADPKD (Aim 3). Disease modifiers to severe disease, via biallelic ADPKD, and due to alleles at other loci will also be identified and characterized in the cellular assay and in vivo in combination with the Pkd1 hypomorphic, RC model. The final aim will exploit the newly identified information that some PKD1 and PKD2 VUS are rescuable, folding mutations that in a maturation-fostering environment can traffic and function appropriately. A screening scheme based on the level of cell surface PC1 will be improved and new chaperone drugs specific for the PC complex will be sought in collaboration with Sanford Burnham Prebys. A second mutation group that will be explored therapeutically are nonsense mutations. A cellular assay for readthrough efficiency is being developed and will be used for screening. Identified chaperone or readthrough drugs will be tested in available mouse models. Overall this proposal will better explain the etiology and the genetic causes of phenotypic variability in ADPKD/ADPLD, develop better prognostic tools for individual selection of patients for treatment that are now becoming available, and explore allele based treatments for ADPKD.

常染色体显性多囊性肾脏疾病（ADPKD）是一种常见的单相关性疾病 逐渐囊肿的发展并导致50％的患者在60岁时导致终阶段肾衰竭（ESRD）。 但是，存在相当大的表型变异性，从子宫发作延伸到足够的患者 肾功能到老年。通常定义的常染色体显性多囊肝病（ADPLD） 导致PLD的最小肾囊肿。从经典上讲，有两个ADPKD基因PKD1和 PKD2，编码PC1和PC2，以及两个ADPLD基因，PRKCSH和SEC63，但在过去的几年中 已经描述了更大的遗传异质性，现在总体实施了九个基因。最新数据 指示与ADPKD和ADPLD相关的病因和发病机理的重叠，并有效 两种疾病中心的PC复合物的生物发生和定位。在最后的资金期间 鉴定出一种新型基因Ganab，它与两种疾病有关，其中编码的蛋白质是GII是 参与PC1的成熟和贩运。 在此提案中，我们将利用下一代测序的进步（NGS） 方法，大量已组装的ADPKD和ADPLD患者 筛选出经典基因，以寻找这些疾病的新基因（AIM 1）。相关的表型 这些基因将被描述（AIM 3）及其作用机理（AIM 2）。 NGS方法将 非常适合筛选分段重复的基因座PKD1，并在已知的 基因座，包括由于镶嵌物引起的某些单元中存在的基因座（AIM 1）。许多PKD1的意义 难以评估不截断的变体（归类为未知意义的变体； vus），但是 最近的证据表明，有些是不完全渗透的等位基因部分解释了PKD1的表型变异性 人群。在AIM 2中改善了计算机预测，结合机器学习，将改善 了解VU的致病性和外观。生物发生和运输的细胞评估 该PC复合物也将用于量化VU的渗透率。发病机理的机理 将在具有超低渗透剂（ULP）PKD1或PKD2等位基因的动物模型中探索。雇用大 将定义在临床上，成像和遗传定义明确的患者种群表型分组 然后将将其与Genic和PKD1等位基因组进行比较（AI​​M 3）。这个迭代过程将允许 与要完善的每个PKD1 VU相关的变体分数（VS）。在另一个人群中，修订的VS， 将聘请单独并与临床，功能和成像数据结合使用以生成A ADPKD的全面，预测算法（AIM 3）。通过生物疾病的疾病改性剂对严重疾病 ADPKD，并且由于其他地区的等位基因，还将在细胞测定和体内进行鉴定和表征 结合PKD1型肌电RC模型。最终目标将利用新近确定的 某些PKD1和PKD2 VU是可救出的信息，在成熟的折叠突变 环境可以适当地交通和功能。基于细胞表面PC1水平的筛选方案 将改进，并将与PC综合大楼特有的新伴侣药物合作感知 Sanford Burnham Prebys。第二个突变组将被热探索是胡说八道 突变。正在开发用于读取效率的细胞测定法，并将用于筛选。 可用的鼠标模型将测试已识别的伴侣或读取药物。总的来说，这个建议将 更好地解释ADPKD/ADPLD中表型变异性的病因和遗传原因，发展更好 用于个人选择治疗患者的预后工具，这些工具现已上市，并探索 基于等位基因的ADPKD治疗。