Genetic Regulation of Valproic Acid Teratogenicity

描述(由申请人提供)： 宫内暴露于药物化合物Depakene(丙戊酸；VPA)会增加人类先天性畸形和神经发育缺陷的发生率。这项研究的目的是鉴定和表征丙戊酸诱导的神经管缺陷(NTDS)的遗传修饰物。这项拟议的研究是在小鼠模型中进行的，但由此产生的数据有望使临床医生在FDA批准的情况下，根据人类患者群体中同源基因变异带来的风险，开发个性化的药物策略。这一点越来越重要，因为VPA现在不仅用于癫痫治疗，而且还用于治疗偏头痛、双相情感障碍和分裂情感障碍，增加了对育龄妇女的接触。我们假设NTDS和神经发育缺陷的病因学涉及胎儿的遗传贡献，并且他们的蛋白产物正在改变VPA诱导神经异常的能力。具体地说，我们建议测试这一假设，即在暴露于致畸浓度的VPA后，患有NTDS的小鼠胚胎中酰基辅酶A合成酶中链(ACSM)基因的变异比类似暴露于看起来正常的胚胎中更普遍。我们建议利用我们已建立的VPA致畸小鼠模型，精细定位7号染色体上的关键区域，以确定与VPA引起的NTDS和神经发育缺陷有关的新基因变异。我们建议在子宫内暴露于VPA之后，对所有已知的基因重新排序，这些基因被映射到受影响和未受影响的小鼠胚胎的关键区域。Sanger测序和下一代测序技术的靶向重测序相结合，使用样本的靶向浓缩(NimbleGen序列捕获阵列和Agilent Technologies SureSelect系统)，将用于彻底询问VPA敏感性基因座。在下一代测序之前，靶向浓缩的目标是扩展我们的全基因组关联研究，以：1)定义SNPs和独特的基因组变异；以及2)将这些变异与VPA诱导的神经发育疾病相关联。然后，我们将利用现有的靶向胚胎干细胞克隆开发新的ACSM突变小鼠系，并验证该基因家族是否调节VPA诱导的NTDS的易感性。

DESCRIPTION (provided by applicant): The in utero exposure to the pharmaceutical compound Depakene (Valproic Acid; VPA) increases the incidence of congenital malformations and neurodevelopmental defects in humans. The objective of this research proposal is to identify and characterize the genetic modifiers of VPA-induced neural tube defects (NTDs). The proposed research is conducted in mouse models, but the resultant data is expected to enable clinicians, under FDA approval, to develop personalized medicine strategies based on an the risk posed by homologous gene variants in human patient populations. This is increasingly important as VPA is now used not only in epilepsy therapy, but also to treat migraine headaches, and bipolar and schizoaffective disorders, increasing exposure to women of reproductive age. We hypothesize that the etiology of NTDs and neurodevelopmental deficits involves fetal genetic contributions, and that their protein products are modifying the ability of VPA to induce neural abnormalities. Specifically, we propose to test the hypothesis that variation within Acyl-CoA Synthetase Medium-Chain (ACSM) genes are more prevalent in mouse embryos with NTDs following exposure to teratogenic concentrations of VPA, than in similarly exposed embryos that appear normal. We propose to fine map the critical region on chromosome 7 in order to identify novel gene variants responsible for NTDs and neurodevelopmental deficits induced by VPA, using our established mouse models of VPA-teratogenesis. We propose to re-sequence all known genes mapped to the critical region in affected and unaffected mouse fetuses following in utero VPA exposure. A combination of Sanger sequencing and targeted resequencing by next-generation sequencing techniques, using targeted enrichment (NimbleGen Sequence Capture Arrays and Agilent Technologies SureSelect System) of samples will be used to thoroughly interrogate the VPA-sensitivity loci. The goal of target enrichment prior to next-generation sequencing is to expand upon our whole genome association studies to: 1) define SNPs and unique genomic variations; and 2) correlate these variants to VPA-induced neurodevelopmental disease. We will then develop novel ACSM mutant mouse lines using existing targeted embryonic stem cell clones and validate this gene family as regulating susceptibility to VPA-induced NTDs.