TGFβ1 rs1800469 and SMAD4 rs10502913 polymorphisms and genetic susceptibility to colorectal cancer in Bangladeshi population

Background: Among Bangladeshi males and females, colorectal cancer is the fourth and fifth most prevalent cancer, respectively. Several studies have shown that the transforming growth factor beta 1 (TGFβ1) gene and SMAD4 gene have a great impact on colorectal cancer.

Objective: The present study aimed to investigate whether TGFβ1 rs1800469 and SMAD4 rs10502913 genetic polymorphisms are associated with susceptibility to colorectal cancer in the Bangladeshi population.

Methods and materials: This case-control study was performed on 167 colorectal cancer patients and 162 healthy volunteers, and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was employed for genotyping.

Results: In case of SMAD4 rs10502913 G > A polymorphism, the A allele reduced the colorectal cancer risk significantly (adjusted OR 0.35, 95% CI 0.23-0.52, p < 0.001) when compared to the G allele. It was also found that G/A and A/A genotypes of SMAD4 rs10502913 G > A polymorphism reduced the risk of colorectal cancer in comparison to the G/G genotype (G/A vs. G/G: adjusted OR 0.24, 95% CI 0.12-0.45, p < 0.001 and A/A vs. G/G: adjusted OR 0.06, 95% CI 0.02-0.21, p < 0.001). TGFβ1 rs1800469 C > T polymorphism showed an elevated risk of developing colorectal cancer, although the results were not statistically significant.

Conclusion: This study confirms the association of SMAD4 rs10502913 gene polymorphism with colorectal cancer susceptibility among the Bangladeshi population.