Table I.
Characteristics of the included studies in the meta-analysis.
| Case genotypes | Control genotypes | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| First author, year | Country | Ethnicity | Cancer type | Diagnostic method | Source of controls | Genotyping | CC | CG | GG | CC | CG | GG | PHWE | NOS score | (Refs.) |
| Ma, 2013 | China | Asian | TNBC | Histopathological | HB | MassARRAY | 126 | 52 | 4 | 136 | 45 | 8 | 0.098 | 7 | (13) |
| Xiong, 2014 | China | Asian | Cervical | Histopathological | HB | PCR-LDR | 91 | 15 | 1 | 151 | 51 | 6 | 0.507 | 6 | (15) |
| You, 2011 | China | Asian | ESCC | Histopathological | PB/HB | MALDI-TOF-MS | 166 | 69 | 9 | 105 | 72 | 4 | 0.037 | 6 | (16) |
| Yin, 2013 | China | Asian | ESCC | Histopathological | HB | PCR-LDR | 454 | 146 | 11 | 470 | 168 | 19 | 0.400 | 7 | (14) |
| Zhang, 2014 | China | Asian | ESCC | Histological | PB | SNaPshot | 803 | 295 | 11 | 910 | 331 | 34 | 0.555 | 8 | (17) |
TNBC, triple-negative breast cancer; ESCC, esophageal squamous cell carcinoma; HB, hospital-based; PB, population-based; HWE, Hardy-Weinberg equilibrium; PCR-LDR, polymerase chain reaction-based ligase detection reaction; NOS, Newcastle-Ottawa Quality Assessment Scale.