本文对47例散发性食管癌中P16基因的第二外显子 ,先用外侧引物扩增进行缺失筛查 ,再用三对内侧引物扩增经首次外侧引物扩增所得的PCR的产物 ,进行套式PCR结合SSCP及PCR直接银染测序技术检测突变。结果检出食管癌中有2例缺失 ,5例突变。在检测出的食管癌的突变中 ,我们发现所有的突变均为125位密码子的错义突变 ,为CGG→CTG的颠换 ,使p16蛋白该位的碱性的精氨酸变为酸性的亮氨酸。这一结果提示P16基因可能与食管癌的发生密切相关。本文参考P16基因的结构功能区对所测突变进行了讨论 ,提出了进一步研究的设想 This article 47 cases of sporadic esophageal cancer in the second exon of P16 gene, first amplified with primers for deletion screening, and then amplified with three pairs of primers for the first time by the outer primer PCR products carried out Nested PCR combined with SSCP and PCR direct silver staining to detect mutations. Results There were 2 cases of esophageal cancer and 5 cases of mutations. Among the detected mutations in esophageal cancer, we found that all the mutations were missense mutations at codon 125, which was the transversion of CGG → CTG, rendering the basic arginine at this position of p16 protein acidic Leucine. This result suggests that P16 gene may be closely related to the occurrence of esophageal cancer. In this paper, the structural mutations of P16 gene are discussed in this paper, and the tentative suggestions for further research are put forward