The MDR1/ABCB1 gene rs 1045642 polymorphism in colorectal cancer

Colorectal cancer (CRC) is one of the most frequently diagnosed tumors in Western countries. CRC is a heterogeneous group of tumors with regards to its molecular pathogenesis and genetic factors. Both genetic variations and anthropometric factors may affect morbidity in CRC patients. The aim of this study was to assess the impact of multidrug resistance 1/ATP-binding cassette sub-family B member 1 gene (MDR1/ABCB1) polymorphism rs1045642 and general anthropometric factors on the CRC risk.

The study included 250 patients who underwent colonoscopy and polypectomy between 2006 and 2013 in a single endoscopy unit in Warsaw, Poland.

The CRC was diagnosed in 50 individuals, and 200 patients were included in the control group. Cases and controls were matched for mean age and sex (p > 0.05). Factors that were found to significantly increase the risk of CRC were ulcerative colitis (8/35 in the CRC group vs. 8/181 in the control group; p = 0.001), family history of CRC (11/33 vs. 26/172; p = 0.05), and diabetes mellitus (12/34 vs. 28/170; p = 0.04). Allele T of the rs 1045642 polymorphism was more frequently present in CRC cases (in both a co-dominant and recessive model) and in males (in a co-dominant model), although these associations were not statistically significant (p > 0.05).

The MDR1/ABCB1 gene polymorphism rs 1045642 may be involved in the pathogenesis of CRC and this relationship may be sex-specific for males. However, further population studies are necessary to assess this relationship.