BACKGROUNDLung cancer is one of the most common cancers worldwide and its mortality rate has increased year after year. Molecular biology has contributed to make people's understanding to the disease at the gene level. A new idea will be given to the early diagnosis and treatment for lung cancer with the method of molecular biology which can be used to find the association between some genes and lung cancer. The aim of this study is to evaluate the relationship between polymorphism of codon 72 (BstU I single nucleotide polymorphism, BstU I SNP) in p53 gene and susceptibility and radiosensitivity of non-small cell lung cancer (NSCLC) in Chinese population.

METHODSThe BstU I single nucleotide polymorphic sites at condon 72 in exon 4 of p53 gene in 50 patients with NSCLC as well as 50 healthy controls were inspected by polymerase chain reaction-restricted fragment length polymorphism assay and the relationship between BstU I SNP and susceptibility and radiosensitivity of NSCLC was analysed by case-control test.

RESULTSThe allelic distribution of the three genotypes (A1/A1, A1/A2, A2/A2) in healthy controls was 32.0%, 42.0% and 26.0% respectively, which differed slightly from that of lung cancer patients, which was 28.0%, 32.0% and 40.0%. These allelic and genotype differences between control and lung cancer groups (A1/A1 OR=0.83, 95% CI 0.36-1.27 and A2/A2 OR=1.90, 95% CI 0.82-4.42) were insignificant. The patients with A1/A1 or A2/A2 genotype were sensitive to radiotherapy and the patients with A1/A2 were not sensitive to radiother-apy (Chi-square=9.2, P < 0.05), the effective rate to radiotherapy were 71.4%, 70.0% and 25.0% respectively.

CONCLUSIONSThere is no significant relationship between the BstUI SNP in p53 and susceptibility in NSCLC .The p53 BstU I SNP is closely associated with radiosensitivity of NSCLC in the Northern Chinese population.