title: TP53 polymorphisms in sporadic North Indian breast cancer patients.
abstract: BACKGROUND
  The purpose of this study was to evaluate the potential association of five (p.P47S, p.R72P, PIN3 Ins16bp, p.R213R and r.13494g>a) polymorphisms of TP53 with the risk of developing breast cancer in North Indian Punjabi population.
  
  
  METHODS
  We screened DNA samples of 200 sporadic breast cancer patients (197 females and 3 males) and 200 unrelated healthy, gender and age matched individuals for the polymorphisms.
  
  
  RESULTS
  For the p.P47S polymorphism, we observed the PP genotype in 99.5% of the patients and PS genotype in only 1 patient. All the controls had the wild type PP genotype. The frequency of RR, RP and PP genotype of p.R72P was 23.5% vs 33.5%, 51.5% vs 45.5% and 25% vs 21% in patients and controls respectively. Heterozygous (RP) genotype was increased in breast cancer patients as compared to controls (51.5 vs 45.5%) and showed 1.61 fold significantly increased risk for breast cancer (OR=1.61, 95% CI, 1.01-2.58, p=0.04). In breast cancer patients the frequencies of A1A1, A1A2 and A2A2 genotypes of PIN3 Ins16bp polymorphism were 67%, 26% and 7% respectively whereas in controls the genotype frequencies were 68.5%, 27.5% and 4% respectively, with no significant difference. For p.R213R (c.639A>G), all individuals had homozygous wild type genotype. The frequencies of GG, GA and AA genotypes of TP53 r.13494g>a polymorphism were 62 vs 67.5%, 33 vs 28% and 5 vs 4.5% in patients and controls respectively, again without significant difference. We observed that RP- A1A1 genotype combination of p.R72P and PIN3 Ins16bp and RP-GG combination of p.R72P and r.13494g>a polymorphism showed significant risk of breast cancer (OR=1.65, 95%CI: 0.98-2.78, p=0.05; OR=1.72, 95%CI: 1.01-2.92, p=0.04).
  
  
  CONCLUSIONS
  The results of present study indicated that among the five TP53 polymorphisms investigated, the p.R72P polymorphism, and the RP-A1A1 and RP-GG genotype combination contribute to breast cancer susceptibility in North Indians.
authors.affiliation: Human Cytogenetics Laboratory, Department of Human Genetics, Guru Nanak Dev University, Punjab, India E-mail : guleria_k@yahoo.com.
authors.forename: Sarika
authors.initials: S
authors.lastname: Sharma
authors.forename: Vasudha
authors.initials: V
authors.lastname: Sambyal
authors.forename: Kamlesh
authors.initials: K
authors.lastname: Guleria
authors.forename: Mridu
authors.initials: M
authors.lastname: Manjari
authors.forename: Meena
authors.initials: M
authors.lastname: Sudan
authors.forename: Manjit Singh
authors.initials: MS
authors.lastname: Uppal
authors.forename: Neeti Rajan
authors.initials: NR
authors.lastname: Singh
authors.forename: Darpan
authors.initials: D
authors.lastname: Bansal
authors.forename: Arun
authors.initials: A
authors.lastname: Gupta
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000235:genetics*; D018567:Breast Neoplasms, Male / Q000235:genetics*; D016022:Case-Control Studies; D005260:Female; D005787:Gene Frequency; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D006801:Humans; D007194:India; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D016159:Tumor Suppressor Protein p53 / Q000235:genetics*
chemical_list: C495901:TP53 protein, human; D016159:Tumor Suppressor Protein p53