Author/Authors :
Akbari, Zahra Gastroenterology and Liver Diseases Research Center - Research Institute for Gastroenterology and Liver Diseases - Shahid Beheshti University of Medical Sciences - Tehran, Iran , Safari-Alighiarloo, Nahid Endocrine Research Center - Institute of Endocrinology and Metabolism - Iran University of Medical Sciences - Tehran, Iran , Asadzadeh Aghdaei, Hamid Basic and Molecular Epidemiology of Gastrointestinal Disorders Research Center - Research Institute for Gastroenterology and Liver Diseases - Shahid Beheshti University of Medical Sciences - Tehran, Iran , Vahedi, Mohsen Department of Epidemiology and Biostatistics - School of Public Health - Tehran University of Medical Sciences - Tehran, Iran , Montazer Haghighi, Mahdi Gastroenterology and Liver Diseases Research Center - Research Institute for Gastroenterology and Liver Diseases - Shahid Beheshti University of Medical Sciences - Tehran, Iran , Matani Borkheili, Maryam Gastroenterology and Liver Diseases Research Center - Research Institute for Gastroenterology and Liver Diseases - Shahid Beheshti University of Medical Sciences - Tehran, Iran , Nazemalhosseini-Mojarad, Ehsan Gastroenterology and Liver Diseases Research Center - Research Institute for Gastroenterology and Liver Diseases - Shahid Beheshti University of Medical Sciences - Tehran, Iran , Zali, Mohammad Reza Gastroenterology and Liver Diseases Research Center - Research Institute for Gastroenterology and Liver Diseases - Shahid Beheshti University of Medical Sciences - Tehran, Iran
Abstract :
Our aim was to investigate the association between two single nucleotide polymorphisms (SNPs) of SMAD7 and the risk of
CRC among Iranian individuals.
Background: Genome-wide association studies (GWAS) have identified 18q21 as a risk locus for colorectal cancer (CRC), which
maps to the SMAD7 gene.
Methods: This case–control study was conducted on 109 CRC cases and 109 controls in the Iranian population to evaluate the
influence of two SNPs of SMAD7, rs2337106 and rs6507874, on the risk of CRC as well as on clinicopathological features. Genotype
determination was performed by TaqMan assay via an ABI 7500 Real Time PCR System (Applied Biosystems) for the DNA of
peripheral blood. Descriptive analysis and logistic regression model were used for statistical analyses.
Results: Genotyping of the SNPs in the SMAD7 gene revealed that the frequency of G allele of rs2337106 was 53.7% in controls and
56.4% in cases (p-value=0.564) while the frequency of C allele of rs6507874 was 55.5% in controls and 56.3% in cases (pvalue=
0.772). Further, there were no significant differences in genotype frequencies of these SNPs between CRC patients and
controls. The SMAD7 genotypes were not associated with the risk of CRC or with any clinicopathological characteristics such as
tumor site, tumor grade, and stage TNM in CRC patients (p-value>0.05), even after adjustment for sex, age, and smoking status.
Conclusion: Our results provided the first evidence that SMAD7 genotypes, rs2337106 and rs6507874, could not be predisposing
markers in genetic susceptibility to CRC in an Iranian population, at least in the studied population.
