Germline polymorphisms of genes involved in different steps of
tumorigenesis like p53, the tumor suppressor gene, are reported to determine the individual susceptibility to
cancer.
Lung cancer is one of the most common and lethal
cancers and tobacco smoking remains its most important etiologic factors. The most frequently p53 mutated
codons of
lung cancer are 72 (exon 4) and 249 (exon 7). Since mutations in the p53 gene are present in approximately 40% of all human
lung cancers and are more common in smokers than in nonsmokers, we aimed to detect the status of p53 at
codon 72 for
Arg/Arg or
Arg/Pro or
Pro/Pro allele polymorphism and p53
codon 249 mutation in smokers and nonsmokers of South India. Allele frequencies in the nonsmokers were 0.16 for the
Arg/Pro allele and 0.84 for the
Pro/Pro allele in our study population. Among the smokers, the frequencies of the
Arg/Pro,
Arg/Arg, and
Pro/Pro alleles were 0.88, 0.04, and 0.08, respectively. No mutation was detected in both smokers and nonsmokers in p53
codon 249. From the worldwide scenario, it can be speculated that the smokers, with
Arg/Pro genotype are more prone for
lung cancer or to other types of
cancer.