Table 1. Characteristics of the 16 studies included in the meta-analysis.
| Author | Year | Country | Ethnicity | Age, years Mean ± SD or Mean (Range) | Samplesn | Genotyping method | ||
| Cases | Controls | Cases | Controls | |||||
| Che, et al. | 2010 | China | Chinese Han | / | / | 115 | 156 | PCR-Sequencing |
| Chen, et al. | 2010 | China | Taiwanese | 56.7±18.7 | 53.9±11.5 | 184 | 184 | PCR-Sequencing |
| Dalgic, et al. | 2011 | Turkey | Turkish | 8.11±4.89 | 8.52±4.55 | 124 | 200 | PCR-RFLP |
| Etokebe, et al. | 2010 | Croatia | Croatian Caucasian | 51.03±18.71 | 41.84±11.90 | 186 | 551 | PCR-Sequencing |
| Jin, et al. | 2007 | China | Chinese Han | 26–63 | 19–55 | 170 | 199 | PCR-SSP |
| Ma, et al. | 2010 | China | Chinese Han | 34.75±16.67 | 38.17±17.39 | 543 | 544 | PCR-RFLP |
| Ma, et al. _a | 2007 | United States | African American | / | / | 339 | 194 | PCR-Sequencing |
| Ma, et al. _b | 2007 | United States | European American | / | / | 180 | 110 | PCR-Sequencing |
| Ma, et al. _c | 2007 | United States | Hispanic American | / | / | 375 | 114 | PCR-Sequencing |
| Ogus, et al. | 2004 | Turkey | Turkish | 35.4±13.5 | 35.9±14.8 | 151 | 116 | PCR-SSP |
| Salvaraj, et al. | 2010 | India | Dravidian | 34.92±11.42 | 32.33±9.75 | 206 | 212 | PCR-RFLP |
| Sanchez, et al. | 2010 | Colombia | Colombian | 39 (26–51) | 42 (25–54) | 499 | 320 | PCR-MS |
| Thuong, et al. | 2007 | Vietnam | Vietnamese | / | / | 358 | 389 | PCR-MS |
| Uciechowski, et al. | 2011 | Germany | German | 58.5±16.8 | 30.5±7.7 | 45 | 49 | PCR-Sequencing |
| Xue, et al. | 2010 | China | Chinese Han | 39.5±17.9 | 26.3±8.5 | 205 | 203 | PCR-Sequencing |
| Yu | 2008 | China | Chinese Han | / | / | 77 | 75 | PCR-RFLP |
PCR = polymerase chain reaction; SSP = sequence-specific primers; RFLP = restriction fragment length polymorphism; MS = mass spectroscopy.