Identifying Thrombosis Modifier Genes in the Mouse

鉴定小鼠血栓形成修饰基因

• 批准号: 7657076
• 负责人: David Ginsburg
• 金额: $ 37.62万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-04-01 至 2014-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7657076
• 关键词: Alleles; Animals; Behavior Therapy; Blood; Blood Clot; Blood Coagulation Disorders; Blood coagulation; Breeding; Chromosome Mapping; Clinical; Development; Diagnostic; Disease; Disease susceptibility; Ethylnitrosourea; Factor V Leiden mutation; Female; Funding; Genes; Genetic; Genetic Crosses; Genetic Variation; Genome; Genotype; Hemorrhage; Heterozygote; Human; Inbred Strains Mice; Infertility; Inherited; Injection of therapeutic agent; Knock-out; Knockout Mice; Maps; Metalloproteases; Molecular Genetics; Morbidity - disease rate; Mouse Strains; Mus; Mutagenesis; Mutate; Mutation; Pathogenesis; Pathologic; Patients; Perinatal; Phenotype; Predisposition; Prognostic Marker; Regulation; Reporting; Research Personnel; Severities; Source; Suppressor Mutations; Testing; Thrombocytopenic Purpura; Thrombophilia; Thrombosis; Thrombotic Thrombocytopenic Purpura; Variant; Work; base; factor V Leiden; genetic linkage analysis; ilium; insight; male; mammalian genome; mortality; mouse genome; mouse model; mutant; novel strategies; offspring; positional cloning; programs; resistant strain

Identifying Thrombosis Modifier Genes in the Mouse The genetic factors responsible for the highly variable clinical course of patients with factor V Leiden and other forms of thrombophilia are unknown. Aim 1 of this project will identify a large subset of potential thrombosis modifier genes within the mammalian genome using a whole genome ENU mutagenesis strategy in the mouse. We previously reported a uniformly lethal, perinatal thrombosis in mice homozygous for the factor V Leiden mutation (FvQ/Q) and heterozygous for Tfpi (Tfpi+/-). In preliminary studies, we used this phenotype as the basis for a large scale genetic suppressor screen. Mutagenized FvQ/Q males were bred with doubly heterozygote (FvQ/+Tfpi+/-) females and > 6300 surviving G1 offspring genotyped to identify rare FvQ/QTfpi+/- animals who have survived the otherwise uniform perinatal lethality, presumably due to the suppressing effect of a mutated (haploinsufficient) modifier gene. As proof of principal, a genetic cross with TF knockout mice demonstrates that mutation at the TF locus will rescue the lethal FvQ/Q Tfpi+/- genotype. To date, 82 candidate suppressor mutants have been identified. Though most of these mutants have been lost due to decreased survival and/or infertility, genetic mapping for 7 of these lines is in progress and an additional 4 lines are undergoing progeny testing. We will expand this screen to achieve 4-6 fold genome coverage and identify the corresponding genes by positional cloning. Aim 2 will further characterize a strain specific modifier of the FvQ/QTfpi+/- lethal phenotype identified in the DBA/2J strain, by a similar positional cloning strategy. Aim 3 will take advantage of natural strain variation in the mouse to identify genetic factors critical for susceptibility to thrombotic thrombocytopenic purpura (TTP). Previous work by us and others suggests that deficiency of the metalloprotease ADAMTS13 is necessary, but not sufficient for the development of TTP in humans and in mice. In preliminary studies, we have shown that the development of TTP in ADAMTS13 null mice is dependent on genetic factors differing among mouse strains. Genetic crosses between susceptible and resistant strains will be performed to identify the underlying gene(s), which should provide critical insight into the pathogenesis of TTP as well as offering candidates for useful diagnostic and prognostic markers in humans. Relevance: These studies should provide new insight into the regulation of blood clotting, and identify a number of genes that may be important predictors of severity for many common inherited blood clotting diseases. This information may also suggest new approaches to therapy for these conditions.

鉴定小鼠中的血栓形成修饰剂基因 导致因子V莱登和 其他形式的血栓形成是未知的。该项目的目标1将确定大量潜力 使用整个基因组ENU诱变策略，哺乳动物基因组内的血栓形成基因基因 在鼠标中。我们先前报道了小鼠中均匀致死的，围产期血栓形成的纯合子 因子V leiden突变（FVQ/Q）和TFPI（TFPI +/-）的杂合子。在初步研究中，我们使用了 表型是大规模遗传抑制筛查的基础。诱变的FVQ/Q雄性繁殖 与双重杂合子（FVQ/+TFPI +/-）女性和> 6300种幸存的G1后代基因分型识别 罕见的FVQ/QTFPI +/-在原本统一的围产期致死性中幸存下来，大概是由于 突变（单倍弹性）修饰剂基因的抑制作用。作为主要的证明，遗传十字架 用TF敲除小鼠表明，TF基因座的突变将挽救致命的FVQ/Q TFPI +/- 基因型。迄今为止，已经确定了82个候选抑制突变体。尽管大多数这些突变体 由于生存率下降和/或不育而丢失了，其中7条线的遗传图正在进行中 另外4条线正在进行后代测试。我们将扩展此屏幕以达到4-6倍 基因组覆盖范围并通过位置克隆确定相应的基因。 AIM 2将进一步描述 通过类似 位置克隆策略。 AIM 3将利用鼠标中的自然应变变异来识别 遗传因素对血栓性血小板减少性紫癜（TTP）的易感性至关重要。我们以前的工作 其他人则建议金属蛋白酶ADAMTS13的不足是必要的，但不足 人类和小鼠中TTP的发展。在初步研究中，我们表明 ADAMTS13无效小鼠中TTP的发展取决于小鼠菌株之间不同的遗传因素。 将进行易感和抗性菌株之间的遗传杂交以识别基础 基因，应该为TTP的发病机理提供重要的见解，并为候选者提供 人类中有用的诊断和预后标记。 相关性：这些研究应提供有关血液凝结调节的新见解，并确定 对于许多常见的遗传血液凝结可能是严重程度的重要预测指标的基因数量 疾病。这些信息还可能暗示针对这些疾病的新方法。