Following meta-analysis, significant associations were seen for six tumor variants (mutant TP53 and PIK3CA, copy number gain of ERBB2/HER2, CCND1 and FGF3, and chromosomal instability/ploidy) and seven germline polymorphisms: ERCC1 rs3212986, ERCC2 rs1799793, TP53 rs1042522, MDM2 rs2279744, TYMS rs34743033, ABCB1 rs1045642 and MTHFR rs1801133.
We analyzed the C3435T SNP in the MDR1 gene which is associated with altered cellular drug uptake in matched tumor and normal tissues of 45 patients suffering from colorectal carcinoma.
The estimated allele frequencies of functional polymorphisms in(of) exon 21 (2677 G>T, Ala893Ser) and exon 26(3435 C>T, Ilel 142I1e) of the MDR] gene were 0.42 and 0.46 in the controls and 0.54 (p=0.035) and 0.60 (p=0.017) in the MSI-H tumors.