Lack of association of intron 3 16 bp polymorphism of TP53 with breast cancer among Iranian-Azeri patients.
BACKGROUND
p53 gene is a well-known tumor suppressor gene that has several polymorphisms in both its exons and introns. It has been suggested that intron 3 16 bp duplication polymorphism may affect the gene function resulting in reduction or suppression of p53 anti tumor activity. In most case control studies a duplicated allele has been noticeably more frequent in cases rather than controls but there are also conflicting results. The aim of this study was to assess the association of intron 3 16 bp duplication polymorphism of p53 with breast cancer risk among Iranian-Azeri population. We also analyzed the clinicopathological information of patients as an epidemiological description of breast cancer in the north-west of Iran.


METHODS
This case-control study was performed on 221 breast cancer patients and 170 controls. Genomic DNA was extracted from peripheral blood samples and tumor tissues. p53 PIN3 genotype was determined using electrophoresis of PCR products on 8% non-denaturing polyacrylamide gels and silver staining.


RESULTS
In the control and case groups, respectively, 62.9% and 61.1% had no 16 bp insertion (A1A1 genotype), 7.1% and 7.7% had insertion in both p53 alleles (A2A2) and 30% and 31.2% were heterozygous (A1A2). There was no significant difference between genotype frequencies as well as allelic frequencies in two case and control groups.


CONCLUSIONS
According to the result of the present study, the intron 3 16 bp duplication polymorphism of p53 could not be assessed as a marker of risk factor for predisposition to breast cancer in Azeri population. However, a high frequency of A2 allele (22.1%) in our population suggested that intron 3 16 bp duplication polymorphism may be a valuable marker for study in other cancers with well designed large groups.
Department of Cellular and Molecular Biology, School of Biology, College of Sciences, University of Tehran, Tehran, Iran E-mail : montasser20sh@khayam.ut.ac.ir, srna52@gmail.com.
Nasser
N
Pouladi
Shideh Montasser
SM
Kouhsari
Mohammadali Hosseinpour
MH
Feizi
Roghayeh
R
Dehghan
Parvin
P
Azarfam
Davoud
D
Farajzadeh
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000235:genetics* / Q000556:secondary; D016022:Case-Control Studies; D002648:Child; D005260:Female; D005500:Follow-Up Studies; D020440:Gene Duplication; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D007438:Introns / Q000235:genetics*; D007492:Iran; D008207:Lymphatic Metastasis; D008875:Middle Aged; D009367:Neoplasm Staging; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic / Q000235:genetics*; D011379:Prognosis; D012307:Risk Factors; D016159:Tumor Suppressor Protein p53 / Q000235:genetics*; D055815:Young Adult
C495901:TP53 protein, human; D016159:Tumor Suppressor Protein p53