Proteomics and Genetics of Enamel and Dentin

描述（由申请人提供）：患有遗传性牙釉质或牙本质缺陷的患者，由于其牙齿的外观受损，自尊心较低，并认为自己的生活质量较差。他们的牙齿很痛：他们不吃热的食物，冷饮和冰淇淋。一个有牙釉质缺陷的9岁小女孩告诉我们，吃冰淇淋的时候疼得就像“当你把胳膊肘撞错了”。提高我们对正常和病理性牙齿形成的理解，为改善遗传性牙齿疾病的诊断、治疗和治愈提供了最好的长期希望。在本研究中，我们验证了以下三个假设：1）编码专门的釉质和牙本质蛋白的基因缺陷分别导致釉质形成障碍和牙本质形成障碍或牙本质发育不良。 2)全基因组搜索和候选基因的方法可以有效地确定参与遗传性牙科疾病的病因基因。 3)表征成釉细胞转录组和牙釉质和牙本质蛋白质组将识别对牙釉质和牙本质形成至关重要的蛋白质，并提高我们对正常和病理性牙齿形成的分子机制的理解。为了验证这些假设，我们提出了以下两个具体目标：SA 1：确定导致遗传性牙釉质和牙本质缺陷的基因和突变。 SA 2：分离和表征发育中的釉质和牙本质的细胞外基质中的分子。 方法：我们招募非综合征性遗传性牙釉质和牙本质缺陷的家庭，描述他们的表型，并对候选基因进行突变分析，以确定其原因。在可能的情况下，我们将进行全基因组搜索或联合分析，将基因组的一小部分与牙科疾病联系起来。通过表征成釉细胞转录组和通过对釉质和牙本质细胞外基质进行蛋白质组学分析来鉴定新的候选基因，这也表征了蛋白质的结构。 重要性：识别导致非综合征性遗传性牙釉质和牙本质缺陷的全套基因将改变我们分类，诊断和感知这些疾病的方式。候选基因的名单，可能会导致疾病的家庭将优先使用建立基因型-表型相关性。由于治疗结果是在具有定义突变的人中进行评估的，因此诸如牙釉质或牙本质粘合的程序的成功或失败可能与哪个基因突变相关，从而导致治疗计划的改进。未来的遗传分析可能会将这些基因的遗传变化与龋齿易感性联系起来，并为牙齿形成机制提供见解。 公共卫生相关性：有一组特殊基因是制造我们牙齿的牙本质和牙釉质层所需的。干扰这些基因正常表达的突变会导致牙齿变形、疼痛和畸形。我们研究的目的是鉴定这些基因并确定它们的功能。完成拟议的研究将提高对遗传性牙齿缺陷的理解和管理。

DESCRIPTION (provided by applicant): Patients with inherited enamel or dentin defects, because of the disfiguring appearance of their teeth, have low self-esteem and perceive themselves as having an inferior quality of life. Their teeth are painful: they avoid hot foods, cold drinks and ice cream. One 9-year-old girl with defective enamel told us that ice cream hurts like "when you bump your elbow wrong". Advancing our understanding of normal and pathological tooth formation provides the best long-term hope for improvements in the diagnosis, treatment, and cure of inherited dental diseases. In this study we test the following three Hypotheses: 1) Defects in the genes encoding specialized enamel and dentin proteins cause amelogenesis imperfecta and dentinogenesis imperfecta or dentin dysplasia, respectively. 2) Genome-wide searches and candidate gene approaches can efficiently identify genes involved in the etiology of inherited dental disorders. 3) Characterizing the ameloblast transcriptome and the enamel and dentin proteomes will identify proteins critical for enamel and dentin formation and improve our understanding of the molecular mechanisms of normal and pathologic tooth formation. To test these hypotheses we propose the following two Specific Aims: SA 1: Identify genes and mutations that cause inherited defects of enamel and dentin. SA 2: Isolate and characterize molecules in the extracellular matrices of developing enamel and dentin. Approach: We recruit families with non-syndromic inherited defects of enamel and dentin, characterize their phenotypes, and perform mutation analyses on candidate genes to identify their causes. When possible we will perform genome-wide searches or joined analyses to link a small part of the genome to the dental disease. New candidate genes are identified by characterizing the ameloblast transcriptome and by performing proteomic analyses of the enamel and dentin extracellular matrices, which also characterize the proteins' structures. Significance: Identifying the full set of genes that cause non-syndromic inherited defects of enamel and dentin will change the ways we classify, diagnose, and perceive these disorders. The list of candidate genes that might cause the disease in a presenting family will be prioritized using established genoptype- phenotype correlations. As treatment outcomes are evaluated in persons with defined mutations, the success or failure of procedures such as enamel or dentin bonding may correlate with which gene is mutated, leading to improvements in treatment planning. Future genetic analyses may link genetic changes in these genes to susceptibility for dental caries and provide insights into mechanisms of tooth formation. PUBLIC HEALTH RELEVANCE: There is a group of specialized genes that are required to make the dentin and enamel layers of our teeth. Mutations that interfere with the normal expression of these genes cause disfiguring, painful, malformations of the teeth. The objective of our research is to identify these genes and to determine their function. Accomplishing the proposed study will improve the understanding and management of inherited dental defects.