目的 对39例Ⅰ型神经纤维瘤病（NF1）患者基因的部分GTP酶活化蛋白相关功能区（GRD区）的cDNA突变进行研究。方法 应用反转录聚合酶链反应（RT-PCR）分段扩增GRD区域上的cDNA序列,用单链构象多态性（SSCP）及直接测序法对RT-PCR产物进行突变分析。结果 仅发现1例点突变G3918T颠换,导致1306精氨酸（R）变成亮氨酸（L）。结论NF1基因的GRD区可能不是NF1基因突变的热点区域。 Objective To investigate the mutation of some GTPase-associated protein (GRD) regions in 39 cases of type 1 neurofibromatosis patients (NF1). Methods The cDNA sequence of GRD was amplified by reverse transcription-polymerase chain reaction (RT-PCR). The single strand conformation polymorphism (SSCP) and direct sequencing were used to analyze the mutation of RT-PCR products. As a result, only one case of point mutation G3918T translocation was found, resulting in 1306 arginine (R) becoming leucine (L). Conclusion NF1 gene GRD may not be the hot spot of NF1 gene mutation.