PICK1基因突变致癫痫的发病机制及其分子诊断方法研究

Epilepsy is a disease of synchronized discharge dysfunction of neurons. There are more than 900 million of epilepsy patients in China. It has been proved that absence epilepsy is closely related with the regulation of mGluR7a by PICK1. However, the exact pathogenesis is still unclear, and currently there is no proper molecular diagnostic method. Our previous study found chimeric gene mutations of PICK1 in epilepsy patients. In this project, we intend to increase the number of patients studied, and investigate the pathogenesis of epilepsy caused by PICK1 mutations, including the clinical findings and those reported in articles. The plasmids of the mutants of PICK1, ICA69 and mGluR7 were constructed and applied to the cultured neurons, HEK293T and brain tissue sections of PICK1 KO mouse for exploring the mechanism of co-localization, membrane traffic and synaptic plasticity. Based on the further understanding of the pathogenesis of epilepsy, it is possible to establish simple and sensitive molecular diagnostic methods. That is, q-PCR or d-PCR methods will be applied to detect mutations of PICK1 and related genes in epilepsy children as well as their parents. The method, once established, might be also useful for the study of other epilepsy genes or for the molecular diagnostic detection of other diseases. Thus it will be a breakthrough for the etiological diagnosis of epilepsy in children and prenatal guidance will be provided for their parents and relatives.

癫痫是神经元同步放电功能异常的疾病，我国的癫痫患者高达900多万。有研究表明失神性癫痫与PICK1对mGluR7a的调控密切相关，但具体发病机制不清楚，也尚无合适的分子诊断方法。我们的前期研究发现癫痫患儿存在PICK1基因嵌合突变，本课题研究中我们拟进一步增加研究例数，对新发现的和已报道的PICK1突变进行致癫痫发病机制研究。研究中，在构建不同的PICK1突变基因，ICA69和mGluR7等克隆后，分别利用培养的神经元，HEK293T和PICK1 KO小鼠脑组织切片进行共定位，膜运输，神经突触可塑性等机制研究。对癫痫发病机制深入理解的基础上，我们希望建立简便、灵敏的分子诊断方法即利用q-PCR或d-PCR方法检测癫痫患儿和其父母的主要PICK1及相关基因的突变位点。该方法一旦建立，也较易推广到其它癫痫基因或疾病的分子诊断，从而为癫痫性患儿的病因诊断及其父母、家属的优生优育提供指导和依据。

癫痫是神经元同步放电功能异常的疾病，在我国发病率高。特发性癫痫是一种难治性癫痫，约占癫痫患者的 30%左右，患者无明显器质性，很大比例该病患者可能具有癫痫基因遗传或突变背景。研究发现癫痫患儿存在PICK1基因嵌合突变。我们通过增加研究例数，筛查癫痫中PICK1, mGluR7a及相关基因突变，并克隆PICK1调控mGluR7a的关键片段和位点。在分子、细胞和动物不同层面研究发现PICK1基因突变致癫痫的发病机制，并建立TaqMan实时定量PCR和数字PCR检测致癫痫基因突变的方法，该方法能有效提高PICK1基因嵌合突变的检出率，对优生优育和遗传咨询有较大帮助，也较易推广到其它癫痫基因或疾病的分子诊断，从而为癫痫性患儿的病因诊断及其父母、家属的优生优育提供指导和依据。此外课题组基于PICK1展开关于疼痛、脓毒血症和自噬等方面的探索研究，发表相关的文章，取得一定进展。