The Genetics of Endophenotypes and Schizophrenia

描述(由申请人提供)： 神经生物学缺陷作为信息性的内表型标记物，在精神分裂症中已经通过一些不同的范例被证明。神经生理学缺陷在P50事件相关抑制、惊吓反应的脉冲前抑制(PPI)和眼动功能障碍的抗眼跳(AS)任务中显著存在。精神分裂症的神经认知缺陷表现为在CPT、言语记忆和工作记忆测试中表现不佳。这些缺陷中的每一个也在精神分裂症患者的临床未受影响的亲属中被证明，这是证据表明，它们可能反映了疾病的部分遗传风险。非精神病、未用药的精神分裂症患者和分裂型患者的缺陷研究结果证实了这一结论。零假设是，所有6个缺陷都反映了所有精神分裂症患者中单一的、共同的潜在遗传功能障碍。对这一假设的检验需要测量同一组精神分裂症患者先证者及其亲属的所有这些缺陷。如果它们都是同一遗传功能障碍的表现(尽管可能在不同的脑区表达)，那么多变量分析将表明，它们都对亲属和精神分裂症患者的一个维度有贡献。另一种假设是，每个家系中只有一个或一小部分缺陷，这与目前遗传连锁研究中发现的异质性是一致的。在这种情况下，多变量分析将显示不同的衡量标准或其子集加载到不同的维度上。精神分裂症本身很可能是任何个体多重缺陷的结果。因此，这项分析是在精神分裂症患者先证者及其亲属的同一队列中进行的，以利用孟德尔第二定律，该定律认为遗传独立的缺陷是独立分离的。因此，虽然精神分裂症患者的先证者本身有多种缺陷，但如果这些缺陷是由不同的遗传因素造成的，那么他们就会被分离到不同的亲属群体。这个7个站点的协作RO1项目将在5年内收集总共420个家系(1680个受试者)和525个正常受试者(每个站点将贡献这些总数的1/7)。在具体措施中可遗传缺陷的发现将被用来指导下一代精神分裂症遗传学研究。

DESCRIPTION (provided by applicant): Neurobiological deficits that serve as informative endophenotype markers have been demonstrated in schizophrenia by a number of different paradigms. Neurophysiological deficits are prominent in P50 event related suppression, prepulse inhibition (PPI) of the startle response, and the antisaccade (AS) task for eye movement dysfunction. Neurocognitive deficits in schizophrenia are revealed by poor performance on the CPT, verbal memory, and tests of working memory. Each of these deficits has also been demonstrated in clinically unaffected relatives of schizophrenia patients, which is evidence that they may reflect part of the heritable risk for the illness. This conclusion is reinforced by findings of deficits in non-psychotic, unmedicated schizophrenia patients, and schizotypal patients. The null hypothesis is that all 6 deficits reflect a single, common underlying heritable dysfunction in all schizophrenia patients. A test of that hypothesis requires measurement of all of these deficits in the same group of schizophrenia patient probands and their relatives. If they are all manifestations of the same genetic dysfunction (although perhaps expressed in different brain areas), then a multivariate analysis would show that they all contribute to a single dimension in both relatives and schizophrenia patients. An alternative hypothesis is that only one or a small subset of deficits is present in each family, which is consistent with the heterogeneity found in current genetic linkage studies. In that case, the multivariate analysis would show the different measures or subsets of them loading onto different dimensions. Schizophrenia itself is likely to be the result of multiple deficits in any individual. Therefore, the analysis is performed in the same cohort of schizophrenia patient probands and their relatives to take advantage of Mendel's second law, which holds that genetically independent deficits segregate independently. Hence, although schizophrenia patient probands themselves have multiple deficits, if the deficits are caused by different genetic factors, then they will segregate to different groups of relatives. This 7 site collaborative RO1 project will gather a combined total of 420 pedigrees (1680 subjects) and 525 normal subjects over 5 years (each site will contribute 1/7th of these totals). Findings of heritable deficits in specific measures will be used to guide the next generation of studies of the genetics of schizophrenia.