Molecular analysis of Angelman syndrome critical region for detection of new related gene

Angelman综合征（AS）是一种以精神发育迟滞、癫痫发作、动作急促和不适当的大笑为特征的异常综合征。先前我们发现位于15 q11-q13的UBE 3A（E6-AP ubiquitin-protein ligase gene）是AS的候选基因。然而，AS症状与UBE 3A功能的相关性尚不明确，且存在UBE 3A无突变的患者，提示ff多个基因可能参与AS的发病。在本研究中，我们试图找到位于AS区域的未知基因。为了简化AS区域的遗传分析，我们采用了河豚基因组，其大小是人类基因组的七分之一。从河豚基因组文库中分离到UBE 3A和一个新的家族基因。此外，我们还尝试分离了河豚SNRPN、IPW、PAR 4等UBE 3A的邻近基因，并利用PCR扩增技术分离了YAC等大型基因组克隆的插入末端，构建了一种新的高效基因捕获载体。

Angelman syndrome (AS) is one of anomaly syndromes characterized by mental retardation, seizure, jerky movement and inappropriate laughter. Previously, we revealed that UBE3A (E6-AP ubiquitin-protein ligase gene) located in 15q11-q13 is a candidate gene of AS. However, the unclear relevance of AS symptoms and UBE3A function and the existence of patients without UBE3A mutation suggested that ff more than one gene might participate in pathogenesis of AS. In this study, we attempted to find unknown genes located in the AS region. In order to simplify genetic analysis of the AS region, we adopted puffer fish genome whose size was one-seventh of the human genome. Puffer fish UBE3A and a novel family gene were isolated from puffer fish genomic libraries. In addition, puffer fish SNRPN, IPW, PAR4, and other neighbor genes of UBE3A were also attempted to isolate, We also describe a new simple method to isolate insert ends of huge genomic clone such as YAC using PCR amplification and construction of a new efficient vector for gene trapping.