EDNRB和EDN-3基因多态性与先天性巨结肠的相关性研究

目的：研究先天性巨结肠（Hirschsprung’s disease,HD）内皮素受体B（EDNRB）和内皮素-3（EDN-3）基因的特征,探讨EDNRB及EDN-3与HD发病的关系。方法：收集散发性HD80例,健康无便秘史儿童70例作为对照。抽提外周血中DNA,PCR反应扩增EDNRB全部7个外显子和EDN-3基因2个外显子,SSCP分析外显子是否有突变,直接测序确定阳性标本基因突变方式。结果：5个病例在EDNRB第4个外显子上存在同义突变,突变方式均为碱基75487位点上G→A置换（Leu277→Leu）,人群发生率为6.25%,正常对照无此改变;EDN-3上未检测到突变。结论：HD中可检测到EDNRB基因多态性改变。EDNRB可能是HD的易感基因。

Research on ENDRB gene and EDN-3 gene in Hirschsprung's disease

Objective：To determine the characteristics of EDNRB gene and EDN-3 gene in Hirschsprung＇s disease（HD） and probe the relationship between variations of EDNRB gene and EDN-3 gene and HD.Methods：Blood from 80 sporadic HD cases and 70 normal cases as control was collected.DNA was extracted from peripheral white blood cells with standard method and single strand conformation polymorphism analysis of polymerase chain reaction product（PCR-SSCP） was used to analyze exons of EDNRB and EDN-3 gene in all cases,finally DNA sequencing was used to investigate patterns of variations.Results：G→A change in codon 277（Leu277→Leu） was observed in exon 4 of 5 patients with HD,the frequency was 6.25%（5/80）.No changes were found in other exons of EDNRB and EDN-3 gene.Conclusion：The change of EDNRB gene can be detected in patients with HD,and EDNRB gene may play a role in the development of HD.