Genetics of stroke vulnerability in C57BL/6 mouse substrains

中风仍然是一种重要的人类疾病，了解遗传因素， 有助于其对具体个人的影响最终将是有针对性的干预措施的关键。 在人群中进行的研究通常涉及影响卒中发生风险的因素。 对中风严重程度的影响很容易在实验模型中检查， 在小鼠和人类群体中的脆弱性位点支持这种翻译潜力， 分析。我们最近发现，中风易感性的显著差异， C57 BL/6小鼠的相关亚系。在J和ByJ亚株中观察到较小的梗死， 后者起源于N谱系的早期。相比之下， 随后衍生的NCrSlc、NCrl和NJ亚株。初步结果表明， 较大的梗死表型作为显性性状遗传，表明单一的因果突变。 这些近共基因亚株群体仅含有有限的分离遗传库， 可能导致中风严重程度差异的变异。 我们建议在C57 BL/6中鉴定调节中风易感性的基因变异 亚株目标1将生成ByJ、NCrSlc和NCrl的综合序列数据 这些资源还不可获得。由于ByJ和NCrSlc是最 密切相关的亚株，以不同的中风脆弱性，这将定义的最低清单， 候选变体。AIM 2将使用高覆盖率的基因组序列和密集的标记面板 已经可用于J和NJ亚株，以绘制相互影响梗死体积的位点 JxNJ和NJxJ F2杂交后代群体经受永久性局灶性缺血。 将使用ByJ和NCrl亚株的F2杂交来确认该基因座。目标3，使用CRISPR- Cas9方法修复每个候选变体，将建立单个遗传因子， C57 BL/6亚株之间卒中易感性变异的主要来源。

Stroke remains a significant human disease, and understanding the genetic factors that contribute to its impact on specific individuals will ultimately be critical in targeting interventions. Studies in human populations generally address factors affecting the risk of stroke occurrence. Impacts on stroke severity are readily examined in experimental models, and parallel mapping of vulnerability loci in mouse and human populations support the translational potential of such analyses. We have recently identified marked divergence of stroke vulnerability among closely related substrains of the C57BL/6 mouse. Smaller infarcts are seen in the J and ByJ substrains, the latter of which originated early in the N lineage. In contrast, larger infarcts are observed in subsequently derived NCrSlc, NCrl and NJ substrains. Preliminary results establish that the larger infarct phenotype is inherited as a dominant trait, indicating a single causal mutation. These nearly coisogenic substrain populations contain only a limited pool of segregating genetic variants that could underlie the difference in stroke severity. We propose to identify the gene variant that modulates stroke vulnerability among C57BL/6 substrains. Aim 1 will generate comprehensive sequence data for ByJ, NCrSlc and NCrl substrains, for which such resources are not yet available. Since ByJ and NCrSlc are the most closely related substrains to differ in stroke vulnerability, this will define the minimum list of candidate variants. Aim 2 will use high-coverage genomic sequences and a dense marker panel already available for J and NJ substrains to map the locus impacting infarct volume in reciprocal populations of JxNJ and NJxJ F2 intercross progeny subjected to permanent focal ischemia. This locus will be confirmed using F2 crosses of ByJ and NCrl substrains. Aim 3, using CRISPR- Cas9 methodology to repair each candidate variant, will establish the single genetic factor that is the main source of variation in stroke vulnerability among C57BL/6 substrains.