Table 2

- Genetic risks for colorectal cancer in Saudi patients.

Genetic lociStudy approachNumber of CRC casesMolecular methodologiesRisk patternsReferences
ABCC1 C218TCase-controlN=51, 65 controlsPCR-RFLP and DNA sequencing (Sanger)Increased CRC risk, OR=3.440
ADIPOQ G276TCase-controlN=60, 60 controlsPCR-RFLPIncreased CRC risk, OR=2.6441
CYP1A1wt/*2ACase-controlN=92, 79 controlsPCR-RFLPIncreased CRC risk, OR=3.6542
GSTM1Case-controlN=80, 78 controlsDiplex PCRIncreased CRC risk, OR=3.743
TP53 rs1042522Case-controlN=80, 78 controlsTaqMan real-time PCR assaysIncreased CRC risk, OR=1.643
KIR 2DS1, 2DS2, 2DS3, 2DS5, and 3DS1Case-controlN=70, 70 controlsPCRIncreased CRC risk, OR=8.6-fold, 3-fold, 2.5-fold, 4.5-fold, and 16.25-fold44
IL17A rs2275913: GA and AA genotypesCase-controlN=117, 100 controlsTaqMan allelic discrimination assay (PCR)Increased CRC risk, OR=2-fold and 2.8-fold45
NOTCH3 rs1043994: G>ACase-controlN=134, 139 controlsTaqMan allelic discrimination assay (PCR)Increased CRC risk in males, OR=1.97146
PARP1 K933N and K945N ‎Case-controlN=50, 50 controlsPCR and Sanger sequencingIncreased CRC risk OR=3.1429 for K933N G>T heterozygote; OR=2.5714 for K945N G>T heterozygote47
PRNCR1 rs1456315: CC genotypeCase-controlN=144, 130 controlsTaqMan assaysIncreased CRC risk, OR=2.0948
RETN rs1862513 and rs375367Case-controlN=60, 60 controlsPCR-RFLPIncreased CRC risk, OR=2.48 (rs1862513); OR=6.5 (rs375367)49
TDG rs4135113Case-controlN=100, 192 controlsTaqMan genotypingIncreased CRC risk, OR>3.6; OR=5 in those >57 years50
TLR9 rs352139Case-controlN=115, 102 controlsTaqMan allelic discrimination assay (PCR)Increased CRC risk for rectal cancers, OR=3.552 and 1.809 for GG genotype and G allele51
TNFA rs361525 (G238A)Case-controlN=100, 100 controlsTaqMan allelic discrimination assayIncreased CRC risk, OR=14.663 for AA genotype and 7.647 for the A allele52
TSLP rs10043985Case-controlN=112, 108 controlsTaqMan genotyping assayIncreased CRC risk, OR=16.52 for AC genotype and 10.837 for the C allele53
VDR1 ApaI rs797232Case-controlN=100, 100 controlsPCR amplification, followed by Sanger sequencingIncreased CRC risk, OR=1.778 in patients >57 years (rs797232 and C allele)54
VDR1 TaqI rs731236Case-controlN=132, 124 controlsPCR-RFLPIncreased CRC risk, OR=6.1855
XRCC1 A399GCase-controlN=100, 100 controlsPCR-RFLP and PCR-CTPPIncreased CRC risk, OR=2.156
ABCB1 G2677TCase-controlN=62, 100 controlsPCR-RFLPReduced CRC risk, OR=0.004 for heterozygotes GT and 0.005 homozygotes TT57
ADIPOQ T45GCase-controlN=60, 60 controlsPCR-RFLPReduced CRC risk, OR=0.41 for the G allele41
CTNNB1 rs4135385Case-controlN=122, 110 controlsTaqMan assaysReduced CRC risk, OR=0.092 for GG genotype58
LRP6 rs2284396Case-controlN=122, 110 controlsTaqMan assaysReduced CRC risk, OR=0.250 for the CC genotype in cases >57 years; OR=0.561 for the C allele58
SFRP3 rs7775Case-controlN=122, 110 controlsTaqMan assaysReduced CRC risk, OR=0.397 for the Gly allele in female gender58
CYP19A1 rs4774585 rs4775936Case-controlN=100, 100 controlsTaqMan genotyping by real-time PCRReduced CRC risk, OR=0.28 for rs4774585 AA genotype in the male gender; OR=0.37 for rs4775936 CT genotype in the female59
IL7R rs1053496Case-controlN=112, 108 controlsTaqMan genotyping assayReduced CRC risk, OR=0.529, 0.467 and 0.644 for the CT and TT genotypes, and the T allele53
PARP1 rs8679Case-controlN=183, 190 controlsTaqMan assayReduced CRC risk, OR=0.566 for the TC genotype and 0.695 for the C allele60
TDG rs1866074 rs3751209Case-controlN=100, 192 controlsTaqMan genotypingReduced CRC risk, OR=0.501 for rs1866074 GG genotype; OR=0.407 for rs3751209 GA genotype in the male gender50
TLR4 rs10759931 rs2770150Case-controlN=115, 102 controlsTaqMan allelic discrimination assayReduced CRC risk, OR=0.052, 0.018 and 0.085 for rs10759931 GA and AA genotypes, and A allele, respectively; OR=0.074, 0.194, 0.188 for rs2770150 TC and CC genotypes, and C allele only in the female gender61
TLR9 rs187084 rs352144Case-controlN=115, 102 controlsTaqMan allelic discrimination assay (PCR)Reduced CRC risk, OR=0.527 for rs187084 T allele in the female gender; OR=0.067 for rs352144 AC genotype for rectal tumours51
VDR1 BsmI rs1544410Case-controlN=100, 100 controlsPCR amplification, followed by Sanger sequencingOR=0.217 for rs1544410 AA genotype and 0.442 for A allele in the female gender54
  • PCR-RFLP: polymerase chain reaction-restriction fragment length polymorphism, CRC: colorectal cancer, OR: odds ratio