BACKGROUND: It is of significance for single nucleotide polymorphisms (SNPs), a difference of rank, which exists widely in biology, genetics and other fields. OBJECTIVE: To detect polymorphism sites in exon-4 of p53 gene, promotor of Fas gene and intron-7 of Fas gene of healthy people in Han nationality in Zhejiang province. DESIGN: Simple random sampling. SETTING: Department of Surgery of the 118 Hospital of Chinese PLA. PARTICIPANTS: A total of 80 healthy people in Han nationality were selected from hospitals in Zhejiang province from August 2005 to January 2006. There were 43 males and 37 females aged from 3 to 78 years with the mean age of 39.5 years, and all subjects were consent. DNA which was used in genetic analysis was selected from peripheral venous blood of all subjects and maintained at -20 ℃. METHODS: Polymorphism sites in exon-4 of p53 gene, promotor of Fas gene and intron-7 of Fas gene were detected with directly DNA sequencing technique. MAIN OUTCOME MEASURES: Polymorphism sites in exon-4 of p53 gene, promotor of Fas gene and intron-7 of Fas gene of healthy people in Han nationality in Zhejiang province. RESULTS: A total of 80 samples were involved in the final analysis. SNPs sites were found at the 119th base of exon-4 of p53 gene (the 72nd codon of p53 gene), the 670th base of upper start codon in promotor of Fas gene (Fas-670), and the 995th base of intron-7 of Fas gene, especially SNPs in the 995th base of intron-7 pf Fas gene, i.e. C→A transversion, was a new site. CONCLUSION: One unknown SNPs site is discovered in intron-7 of Fas gene of people in Han nationality in Zhejiang province. This study also proves that the 72nd codon exists in p53 gene and the -670 polymorphism site exists in promotor of Fas gene. BACKGROUND: It is the significance of single nucleotide polymorphisms (SNPs), a difference of rank, which has widely in biology, genetics and other fields. OBJECTIVE: To detect polymorphism sites in exon-4 of p53 gene, promotor of Fas gene and intron -7 of Fas gene of healthy people in Han nationality in Zhejiang province. DESIGN: Simple random sampling. SETTING: Department of Surgery of the 118 Hospital of Chinese PLA. PARTICIPANTS: A total of 80 healthy people in Han nationality were selected from hospitals in Zhejiang province from August 2005 to January 2006. There were 43 males and 37 females aged from 3 to 78 years with the mean age of 39.5 years, and all subjects were consent. DNA which was used in genetic analysis was selected from peripheral venous blood of all subjects and maintained at -20 ° C METHODS METHODS: Polymorphism sites in exon-4 of p53 gene, promotor of Fas gene and intron-7 of Fas gene were detected with directly DNA sequencing technique. MAIN OUTCOME MEASURES: Polymor phism sites in exon-4 of p53 gene, promotor of Fas gene and intron-7 of Fas gene of healthy people in Han nationality in Zhejiang province. RESULTS: A total of 80 samples were involved in the final analysis. SNPs sites were found at the 119th base of exon-4 of p53 gene (the 72nd codon of p53 gene), the 670th base of upper start codon in promotor of Fas gene (Fas-670), and the 995th base of intron-7 of Fas gene, especially SNPs in the 995th base of intron-7 pf Fas gene, ie C → A transversion, was a new site. CONCLUSION: One unknown SNPs site is discovered in intron-7 of Fas gene of people in Han nationality in Zhejiang province. This study also proves that the 72nd codon exists in p53 gene and the -670 polymorphism site exists in promotor of Fas gene.