EXT1基因1633-26(C→A)突变可能致多发性外生性骨疣

A mutation 1633-26(C→A) in EXT1 gene causes multiple exostoses

目的研究1例散发多发性外生性骨疣患者的基因突变情况,确定其致病基因。方法采用聚合酶链反应结合DNA直接测序法检测EXT1以及EXT2基因的突变热点区域;并应用错配引物PCR扩增引入酶切位点结合限制性片段长度多态性方法检测和鉴定突变。结果经测序证实在患者EXT1基因的第7内含子3′剪接位点上游26bp处发现一杂合突变,此杂合突变不存在于其表型正常的父母双亲中,是一个新生突变;错配引物扩增与限制性片段长度多态性分析结果表明在150名家系外正常对照者中没有此突变。结论EXT1基因1633-26(C→A)突变可能是导致这个患者发生多发性外生性骨疣的致病突变。

Objective To study the gene mutation in a patient with multiple exostoses, identify the diseasecausing gene mutation. Methods Polymerase chain reaction and DNA sequencing were used to screen the EXT1 or EXT2 gene mutation, while mismatch primer amplification and restriction endonuclease digestion were performed to confirm the mutation. Results By DNA sequencing, a mutation in the seventh intron was detected and located at 26 bp of 3＇ splice site upstream in EXT1 gene, which was unreported before. Mismatch primer amplification and restriction flagment length polymorphism analysis suggested that this mutation was not detected in the normal control. Conclusion The mutation 1633-26（C→A） may be the disease-cansing mutation in this patient with multiple exostoses.