Burden and signatures of somatic mutations in genomes of healthy individuals.

健康个体基因组体细胞突变的负担和特征。

基本信息

批准号：
10515317
负责人：
Natalie Saini
金额：
$ 24.9万
依托单位：
MEDICAL UNIVERSITY OF SOUTH CAROLINA
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-11-20 至 2023-10-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10515317
关键词：
Address Alleles Bar Codes Bioinformatics Biological Assay Biopsy Cell Culture Techniques Cell Line Cells Clone Cells CpG dinucleotide Cytidine Deaminase Cytosine DNA DNA Damage DNA Repair DNA Repair Gene DNA Repair Pathway DNA-Directed DNA Polymerase Data Deamination Defect Disease Endogenous Factors Environmental Risk Factor Exposure to Fibroblasts Genes Genetic Genetic Polymorphism Genetic Recombination Genetic Variation Genome Genomic Instability Goals Growth Hair follicle structure Health Human Human Cell Line Human body Individual Intrinsic factor Lead Lesion Lymphocyte Malignant Neoplasms Measures Methylation Minor Mus Mutagenesis Mutagenicity Tests Mutagens Mutation National Institute of Environmental Health Sciences Participant Pathologic Pathologic Mutagenesis Pathology Persons Plasmids Population Predisposition Prevention strategy Process Proteins Registries Reporter Research Personnel Role Sampling Single Nucleotide Polymorphism Site Skin Somatic Cell Somatic Mutation Source Specificity System Testing Tissues Ultraviolet Rays Variant Yeasts biobank cancer genome cancer type carcinogenesis career cell immortalization cell type design disorder prevention exome genetic manipulation genetic variant genome analysis genome sequencing genome-wide individual variation insight knowledge base melanocyte mutant normal aging oxidative damage protein function repaired single molecule real time sequencing tumor whole genome

项目摘要

Somatic mutations accumulate over the lifetime of an individual due to both genetic and environmental factors. It is becoming evident that somatic genome changes are associated with a host of pathologies including cancers. Sequencing genomes of different cancer types suggested that mutation loads vary between cell types and across the body. The variations have been associated with differential exposure to DNA damaging agents and the replicative potential of the cells. In addition, mutation loads due to DNA damaging lesions would also be dependent on the ability of the cells to repair damage in an error-free manner. However, the mutation loads attributable to environmental and intrinsic factors across cell types in healthy individuals are not known. Also, it is not known how polymorphisms within DNA repair genes compromise repair efficiency and alter the mutation landscape in cells exposed to environmental DNA damage as well as in unexposed cells. The goal of this proposal is to determine the extent of somatic genome changes within the body and in different individuals and to examine the mechanisms that contribute to this variability. To address this goal, I will explore the following aims. In Aim1, I will directly analyze the impact of DNA repair polymorphisms associated with cancers on DNA repair capacity using orthogonal systems. Using plasmid-based host cell reactivation assays, I will test repair efficiency in lymphocytes with homozygous minor (mutant) or major (wild-type) alleles. I will also determine if these mutant human genes increase mutation and recombination rates in yeast and human cells upon exposure to exogenous DNA damage and during unchallenged growth. In Aim2, I will determine the role of deleterious single nucleotide polymorphisms (SNPs) in DNA repair genes. Mutations leading to loss of a functional MBD4 glycosylase, have been shown to increase CT changes in CpG dinucleotides in cancer genomes. I will test if SNPs that are predicted to be deleterious to the MBD4 protein also increase mutation loads and altering signatures in somatic cells from healthy individuals. In Aim3, I will estimate mutation loads in different cell-types isolated from the same individuals from different body sites. I will assess the contributions of mutation signatures associated with known environmental and endogenous mutagenic sources to mutation loads in the samples. The completion of the studies in this proposal will provide me with expertise in cell culture, genetic manipulation of human cell lines and bioinformatics, paving the way for a successful career as an independent researcher. Significance: These studies will increase our understanding of the interplay of environmental and genetic factors that determine somatic mutagenesis. These results are important for understanding the susceptibility of individuals to cancers and other diseases associated with somatic mutagenesis, and in designing individual- specific disease prevention strategies.

由于遗传和环境因素，体细胞突变在个体的一生中不断积累。越来越明显的是，体细胞基因组变化与许多病理学相关，包括对不同癌症类型的基因组进行测序表明，细胞之间的突变量有所不同。这些差异与 DNA 损伤的暴露程度不同有关。此外，DNA 损伤性病变导致的突变负荷。还取决于细胞以无差错的方式修复损伤的能力。健康个体中跨细胞类型的环境和内在因素引起的突变负荷并不此外，尚不清楚 DNA 修复基因内的多态性如何影响修复效率。改变暴露于环境 DNA 损伤的细胞以及未暴露的细胞的突变景观。该提案的目标是确定体内和不同环境中体细胞基因组变化的程度。为了实现这一目标，我将研究导致这种差异的机制。探索以下目标。在Aim1中，我将直接分析DNA修复多态性相关的影响。使用正交系统利用基于质粒的宿主细胞再激活来研究癌症的 DNA 修复能力。分析中，我将测试具有纯合次要（突变）或主要（野生型）等位基因的淋巴细胞的修复效率。我还将确定这些突变的人类基因是否会增加酵母和酵母中的突变和重组率在 Aim2 中，我将在暴露于外源 DNA 损伤和不受挑战的生长过程中对人类细胞进行研究。确定有害单核苷酸多态性 (SNP) 在 DNA 修复基因中的作用。导致功能性 MBD4 糖基化酶丧失，已被证明会增加 CpG 中的 CT 变化我将测试癌症基因组中的 SNP 是否对 MBD4 蛋白有害。在 Aim3 中，我会增加突变负荷并改变健康个体体细胞的特征。我将估计从不同身体部位的同一个体中分离出的不同细胞类型的突变负荷。评估与已知环境和内源相关的突变特征的贡献本提案中的研究的完成将影响样品中的突变负荷。为我提供细胞培养、人类细胞系基因操作和生物信息学方面的专业知识，铺平道路作为一名独立研究员的成功职业之路。意义：这些研究将增加我们对环境和遗传相互作用的理解决定体细胞突变的因素这些结果对于了解易感性很重要。个体罹患癌症和其他与体细胞突变相关的疾病，以及设计个体- 具体的疾病预防策略。

项目成果

期刊论文数量（4）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Acetaldehyde makes a distinct mutation signature in single-stranded DNA.

DOI：
10.1093/nar/gkac570
发表时间：
2022-07-22
期刊：
NUCLEIC ACIDS RESEARCH
影响因子：
14.9
作者：
Vijayraghavan, Sriram;Porcher, Latarsha;Mieczkowski, Piotr A.;Saini, Natalie
通讯作者：
Saini, Natalie

Aldehyde-Associated Mutagenesis─Current State of Knowledge.