目的　明确 STK1 1 基因在中国人 Peutz- Jeghers(PJ)综合征的突变特征 ,为建立基因诊断奠定基础。方法　用 DNA直接测序方法 ,对 18个家系的 PJ综合征患者 STK1 1 基因 9个外显子进行研究。结果　在 6个家系中发现 6个使基因产物发生改变的突变 ,推测最终导致产生截短型蛋白。结论　在中国人PJ综合征患者中 STK1 1 基因突变的检出率为 6 /18。突变位点比较广泛 ,2 /3集中在第 1外显子。两代以上发病的家系突变率为 6 6 .7% ,散发病例突变率为 16 .7 Objective To clarify the mutation characteristics of STK1 1 gene in Chinese Peutz-Jeghers syndrome (PJ) syndrome and lay the foundation for the establishment of gene diagnosis. Methods Nine exons of STK1 1 gene from 18 pedigrees with PJ syndrome were studied by DNA direct sequencing. As a result, six mutations in the genealogy were found in six families, presumably leading to the production of truncated proteins. Conclusion The detection rate of STK1 1 mutation in Chinese PJ syndrome patients is 6/18. The mutation site is more extensive, 2/3 concentrated in the first exon. The incidence of family history of more than two generations of incidence of mutation was 66.7%, sporadic cases of mutation rate was 16.7