Association of intron and exon polymorphisms of p53 gene in Iranian patients with gastritis.
OBJECTIVE
The propose of this study was to evaluate the probable correlation between exon and intron polymorphisms of p53 gene and their association with clinicopathological aspects of gastritis.


BACKGROUND
Regarding to the decisive role of p53 in the development of a variety of human cancers, a comprehensive study concerning probable correlation between polymorphisms in the p53 intron and exon in gastritis lesions, may open new insight toward gastric cancer development and prevention.


METHODS
PCR-Sequencing was done for exons and introns 2-7 on the 97 gastritis and normal samples, age range of 15-83 years. Also, microsatellite status was evaluated using five mono nucleotide repeat markers. Variation at codon 72 was associated with IVS2 + 38, p53INS3 and IVS3-29. In addition, IVS2 + 38 had association with polymorphism at codon 36 & 245. Gastritis samples had stable microsatellite except nine patients showing polymorphism for NR-21 and one for Bat-25.


RESULTS
Most of patients with stable microsatellites (83.9%) had allele G at codon72 without p53INS3. In addition, all patients with GA and CG at codon 36 / IVS2 + 38 had stable microsatellites. Severity and activity of gastritis were in association with genotypes combined of codon 36/IVS2 + 38 and 245/IVS2 + 38 respectively. In addition, the profiles of combined variation at codon 72/IVS3-29 and codon 72/IVS6 + 31 were different between patients with ages less and greater than 45 years.


CONCLUSIONS
As, some exon variations of p53 gene specially codon 72, were in association with alterations at introns and their combined genotypes were correlated with microsatellite status, pathological findings and age, therefore, it could be inferred that the these combinations of p53 gene polymorphisms work as a whole, not as single.
Gastroenterology and Liver Diseases Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Rouhallah
R
Najjar Sadeghi
Gastroenterology and Liver Diseases Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Negar
N
Sahba
Basic and Molecular Epidemiology of Gastrointestinal Disorders Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Mohsen
M
Vahedi
Gastroenterology and Liver Diseases Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Seyed
S
Reza Mohebbi
Gastroenterology and Liver Diseases Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Mohammad
M
Reza Zali
Codon 72; Gastritis; Helicobacter pylori; IVS2 + 38; p53 gene