High-throughput mutation analysis for known and novel single-gene causes of kidney stones and related disorders

肾结石疾病包括肾结石症（NL）和肾钙质沉着症（NC）。NL和NC是普通人群中非常普遍的疾病（约10%），与慢性肾脏疾病（CKD）的显著发病率和进展相关。其病因是多因素的，有环境和遗传因素。虽然遗传率估计为56%，并且已经确定了30多个单基因原因，但NL/NC的遗传基础在很大程度上仍然未知。此外，尽管了解NL/NC的分子原因可能对预后、预防和/或治疗有重要影响，但对于大多数NL/NC患者，致病基因的突变分析迄今尚未实现。我们假设单基因原因在肾结石患者中所占的比例明显高于一般的假设。我们最近开发了一种新的高通量突变分析方法，允许以非常低的成本同时检查多个个体的多个基因。在一项初步研究中，我们在268名无关的NL/NC患者中展示了该技术的力量。因此，我们确定了15%（40/268）的分子原因，进一步表明单基因原因在NL/NC中的作用确实被低估了。本研究旨在研究两个主要目标：1)在约600名NL/NC患者的临床明确队列中确定bb30已知单基因原因的患病率，以及表征与CKD发病年龄和表现相关的基因型-表型相关性。2)在未发现已知基因的受试者中，通过全外显子组/基因组测序和候选基因分析鉴定新的疾病基因。本提案的实施将拓宽对NL/NC分子基础的认识。通过识别新的疾病机制，该项目可能有助于开发新的治疗靶点，并有助于建立更个性化的治疗方法。

Kidney stone disease comprises nephrolithiasis (NL) and nephrocalcinosis (NC). NL and NC are highly prevalent conditions in the general population (~10%) associated with significant morbidity and progression to chronic kidney disease (CKD). Its etiology is multifactorial with an environmental and a genetic component. Although the heritability has been estimated to 56% and more than 30 monogenic causes have been identified, the genetic basis of NL/NC remains largely unknown. Furthermore, for most patients with NL/NC, mutation analysis in causative genes has not been accessible so far, despite the fact that knowledge of the molecular cause of NL/NC may have important consequences for prognosis, prophylaxis and/or treatment. We hypothesize that the fraction of monogenic causes to the overall population of kidney stone formers is significantly higher than generally assumed. We recently developed a novel high-throughput mutation analysis approach that allows to simultaneously examine multiple genes in multiple individuals at very low cost. In a pilot-study we demonstrated the power of the technique in 268 unrelated patients with NL/NC. We thereby identified the molecular cause in 15% (40/268), further suggesting that the role of single-gene causes in NL/NC is indeed underestimated. With this proposal we aim to investigate two main goals: 1) Determination of the prevalence of >30 known monogenic causes in a clinically well-defined cohort of ~600 individuals with NL/NC, as well as characterizing genotype-phenotype correlations, related to age-of-onset and manifestation of CKD. 2) Identification of novel disease genes by whole exome/genome sequencing AND candidate gene analysis in subjects without prior findings in known genes. Implementation of this proposal will broaden the knowledge of the molecular basis of NL/NC. By identification of new disease mechanisms, this project may contribute to develop novel therapeutic targets and help to establish a more personalized treatment.