Table 1.
Characteristics of studies included in the meta-analysis
| Study | Year | Country | Ethnicity | Genotype methods | Source of controls | Sample size (case/control) | Case | Control | HWE (P value) | ||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
|
|
||||||||||||
| CC | CT | TT | CC | CT | TT | ||||||||
| Balog [6] | 2005 | Hungary | European | RT-PCR | PB | 77/71 | 22 | 35 | 20 | 21 | 39 | 11 | 0.309 |
| Chao [7] | 2005 | China | Asian | PCR-RFLP | HB | 177/117 | 84 | 82 | 11 | 49 | 62 | 6 | 0.015 |
| Masamune [8] | 2010 | Japan | Asian | PCR-RFLP | PB | 346/319 | 71 | 172 | 103 | 69 | 143 | 107 | 0.106 |
| Tukiainen [9] | 2008 | Finland | European | MALDI-TOF MS | PB | 396/309 | 147 | 182 | 67 | 133 | 129 | 47 | 0.095 |
| Zhang [10] | 2005 | China | Asian | PCR-RFLP | PB | 215/116 | 128 | 59 | 28 | 71 | 32 | 13 | 0.004 |
RT-PCR: real-time polymerase chain reaction; PCR-RFLP: polymerase chain reaction-restriction fragment length polymorphism; MALDI-TOF MS: matrix-assisted laser desorption/ionization time-of-flight mass spectrometry; PB: population-based; HB: hospital-based.