- Genetic risks for colorectal cancer in Saudi patients.
| Genetic loci | Study approach | Number of CRC cases | Molecular methodologies | Risk patterns | References |
|---|---|---|---|---|---|
| ABCC1 C218T | Case-control | N=51, 65 controls | PCR-RFLP and DNA sequencing (Sanger) | Increased CRC risk, OR=3.4 | 40 |
| ADIPOQ G276T | Case-control | N=60, 60 controls | PCR-RFLP | Increased CRC risk, OR=2.64 | 41 |
| CYP1A1wt/*2A | Case-control | N=92, 79 controls | PCR-RFLP | Increased CRC risk, OR=3.65 | 42 |
| GSTM1 | Case-control | N=80, 78 controls | Diplex PCR | Increased CRC risk, OR=3.7 | 43 |
| TP53 rs1042522 | Case-control | N=80, 78 controls | TaqMan real-time PCR assays | Increased CRC risk, OR=1.6 | 43 |
| KIR 2DS1, 2DS2, 2DS3, 2DS5, and 3DS1 | Case-control | N=70, 70 controls | PCR | Increased CRC risk, OR=8.6-fold, 3-fold, 2.5-fold, 4.5-fold, and 16.25-fold | 44 |
| IL17A rs2275913: GA and AA genotypes | Case-control | N=117, 100 controls | TaqMan allelic discrimination assay (PCR) | Increased CRC risk, OR=2-fold and 2.8-fold | 45 |
| NOTCH3 rs1043994: G>A | Case-control | N=134, 139 controls | TaqMan allelic discrimination assay (PCR) | Increased CRC risk in males, OR=1.971 | 46 |
| PARP1 K933N and K945N | Case-control | N=50, 50 controls | PCR and Sanger sequencing | Increased CRC risk OR=3.1429 for K933N G>T heterozygote; OR=2.5714 for K945N G>T heterozygote | 47 |
| PRNCR1 rs1456315: CC genotype | Case-control | N=144, 130 controls | TaqMan assays | Increased CRC risk, OR=2.09 | 48 |
| RETN rs1862513 and rs375367 | Case-control | N=60, 60 controls | PCR-RFLP | Increased CRC risk, OR=2.48 (rs1862513); OR=6.5 (rs375367) | 49 |
| TDG rs4135113 | Case-control | N=100, 192 controls | TaqMan genotyping | Increased CRC risk, OR>3.6; OR=5 in those >57 years | 50 |
| TLR9 rs352139 | Case-control | N=115, 102 controls | TaqMan allelic discrimination assay (PCR) | Increased CRC risk for rectal cancers, OR=3.552 and 1.809 for GG genotype and G allele | 51 |
| TNFA rs361525 (G238A) | Case-control | N=100, 100 controls | TaqMan allelic discrimination assay | Increased CRC risk, OR=14.663 for AA genotype and 7.647 for the A allele | 52 |
| TSLP rs10043985 | Case-control | N=112, 108 controls | TaqMan genotyping assay | Increased CRC risk, OR=16.52 for AC genotype and 10.837 for the C allele | 53 |
| VDR1 ApaI rs797232 | Case-control | N=100, 100 controls | PCR amplification, followed by Sanger sequencing | Increased CRC risk, OR=1.778 in patients >57 years (rs797232 and C allele) | 54 |
| VDR1 TaqI rs731236 | Case-control | N=132, 124 controls | PCR-RFLP | Increased CRC risk, OR=6.18 | 55 |
| XRCC1 A399G | Case-control | N=100, 100 controls | PCR-RFLP and PCR-CTPP | Increased CRC risk, OR=2.1 | 56 |
| ABCB1 G2677T | Case-control | N=62, 100 controls | PCR-RFLP | Reduced CRC risk, OR=0.004 for heterozygotes GT and 0.005 homozygotes TT | 57 |
| ADIPOQ T45G | Case-control | N=60, 60 controls | PCR-RFLP | Reduced CRC risk, OR=0.41 for the G allele | 41 |
| CTNNB1 rs4135385 | Case-control | N=122, 110 controls | TaqMan assays | Reduced CRC risk, OR=0.092 for GG genotype | 58 |
| LRP6 rs2284396 | Case-control | N=122, 110 controls | TaqMan assays | Reduced CRC risk, OR=0.250 for the CC genotype in cases >57 years; OR=0.561 for the C allele | 58 |
| SFRP3 rs7775 | Case-control | N=122, 110 controls | TaqMan assays | Reduced CRC risk, OR=0.397 for the Gly allele in female gender | 58 |
| CYP19A1 rs4774585 rs4775936 | Case-control | N=100, 100 controls | TaqMan genotyping by real-time PCR | Reduced CRC risk, OR=0.28 for rs4774585 AA genotype in the male gender; OR=0.37 for rs4775936 CT genotype in the female | 59 |
| IL7R rs1053496 | Case-control | N=112, 108 controls | TaqMan genotyping assay | Reduced CRC risk, OR=0.529, 0.467 and 0.644 for the CT and TT genotypes, and the T allele | 53 |
| PARP1 rs8679 | Case-control | N=183, 190 controls | TaqMan assay | Reduced CRC risk, OR=0.566 for the TC genotype and 0.695 for the C allele | 60 |
| TDG rs1866074 rs3751209 | Case-control | N=100, 192 controls | TaqMan genotyping | Reduced CRC risk, OR=0.501 for rs1866074 GG genotype; OR=0.407 for rs3751209 GA genotype in the male gender | 50 |
| TLR4 rs10759931 rs2770150 | Case-control | N=115, 102 controls | TaqMan allelic discrimination assay | Reduced 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 gender | 61 |
| TLR9 rs187084 rs352144 | Case-control | N=115, 102 controls | TaqMan 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 tumours | 51 |
| VDR1 BsmI rs1544410 | Case-control | N=100, 100 controls | PCR amplification, followed by Sanger sequencing | OR=0.217 for rs1544410 AA genotype and 0.442 for A allele in the female gender | 54 |
PCR-RFLP: polymerase chain reaction-restriction fragment length polymorphism, CRC: colorectal cancer, OR: odds ratio