title: Murine double minute clone 2,309T/G and 285G/C promoter single nucleotide polymorphism as a risk factor for breast cancer: a Polish experience.
abstract: BACKGROUND
  Breast cancer is a multifactorial disease caused by complex interactions between genetic and environmental factors. Recently, a functional polymorphism, MDM2 285G>C (rs117039649), has been discovered. This polymorphism antagonizes the effect of the 309T>G (rs2279744) polymorphism on the same gene, resulting in decreased MDM2 transcription.
  
  
  METHODS
  The MDM2 285G>C and 309T>G polymorphisms were identified by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and sequencing analysis in women with breast cancer (n=468) and controls (n=550).
  
  
  RESULTS
  The odds ratio (OR) for breast cancer patients with the MDM2 285C/C and 285G/C genotypes was 0.4768 (95% confidence interval [CI] 0.2906-0.7824; p=0.0033, pcorr=0.0066). We also found a significantly lower frequency of the MDM2 285C allele in patients with breast cancer than in controls: the OR for the C allele in patients with breast cancer was 0.4930 (95% CI=0.3059-0.7947, p=0.0031, pcorr=0.0062). The p value of the chi-square test for the trend observed for the MDM2 285G>C polymorphism was statistically significant (ptrend=0.0036). The statistical power of this study amounted to 85% for the G/C or C/C genotypes and 85% for the C allele. However, we did not observe significant differences between the distribution of MDM2 309T>G genotypes and alleles in patients with breast cancer and healthy controls.
  
  
  CONCLUSIONS
  In a sample of the Polish population, we observed that the MDM2 285C gene variant may be a significant protective factor against breast cancer.
authors.affiliation: Department of Biochemistry and Molecular Biology, Poznań University of Medical Sciences, Poznań - Poland.
authors.forename: Piotr
authors.initials: P
authors.lastname: Piotrowski
authors.forename: Margarita
authors.initials: M
authors.lastname: Lianeri
authors.forename: Błazej
authors.initials: B
authors.lastname: Rubis
authors.forename: Hanna
authors.initials: H
authors.lastname: Knuła
authors.forename: Maria
authors.initials: M
authors.lastname: Rybczyńska
authors.forename: Sylwia
authors.initials: S
authors.lastname: Grodecka-Gazdecka
authors.forename: Paweł P
authors.initials: PP
authors.lastname: Jagodziński
mesh_terms: D000818:Animals; D001943:Breast Neoplasms / Q000235:genetics*; D016022:Case-Control Studies; D004195:Disease Models, Animal; D005260:Female; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D008325:Mammary Neoplasms, Experimental / Q000235:genetics; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D008875:Middle Aged; D011044:Poland; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D020641:Polymorphism, Single Nucleotide; D051736:Proto-Oncogene Proteins c-mdm2 / Q000235:genetics*
chemical_list: C497206:MDM2 protein, human; C497207:Mdm2 protein, mouse; D051736:Proto-Oncogene Proteins c-mdm2