Table 1 Main characteristics of all case–control studies included in meta-analysis
Literature | Ethnics (country) | Genotyping methods | Source of control | Sample size | HWE conformity | NOS | Genotype frequency (Case) | Genotype frequency (Control) | Mean age (Case) | Mean age (Control) | Year | ||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
CC | CT | TT | CC | CT | TT | ||||||||||
Seedhouse et al. [15] | Caucasian (United Kingdom) | PCR–RFLP | PB | 123/175 | Yes | 8 | 99 | 87 | 30 | 92 | 64 | 19 | 63 (17–96) | 52 (15–97) | 2002 |
Seedhouse et al. [16] | Caucasian (United Kingdom) | PCR–RFLP | PB | 216/175 | Yes | 8 | 119 | 103 | 38 | 92 | 64 | 19 | 64 (11–96) | 50 (15–97) | 2004 |
Matullo et al. [17] | Caucasian (European countries) | TaqMan | PB | 169/1094 | Yes | 8 | 61 | 90 | 18 | 383 | 544 | 167 | 35–74 | 35–74 | 2006 |
Bhatla et al. [18] | Caucasian (United States) | TaqMan | PB | 282/646 | Yes | 9 | 125 | 157 | 47 | 253 | 309 | 84 | NR | NR | 2008 |
Zhang et al. [19] | Asian (China) | PCR–RFLP | PB | 148/458 | Yes | 7 | 133 | 13 | 2 | 403 | 46 | 9 | 42 (23–76) | 42 (23–76) | 2009 |
Hamdy et al. [20] | African (Egypt) | Direct sequencing | PB | 50/30 | Yes | 6 | 22 | 20 | 8 | 18 | 9 | 3 | 14–65 | 12–46 | 2011 |
Liu et al. [21] | Asian (China) | PCR–RFLP | PB | 379/806 | Yes | 7 | 55 | 39 | 11 | 627 | 73 | 4 | 32 (5–69) | 42 (15–90) | 2011 |
Nina et al. [23] | Caucasian (Slovenia) | TaqMan | PB | 20/39 | Yes | 7 | 6 | 8 | 6 | 15 | 19 | 5 | 9.5 (2–34) | 10 (0–37) | 2012 |
Abramenko et al. [22] | Caucasian (Ukraine) | PCR–RFLP | PB | 159/73 | Yes | 8 | 74 | 60 | 25 | 30 | 33 | 10 | 57.78 ± 1.09 | 58.16 ± 0.91 | 2012 |
Sorour et al. [25] | African (Egypt) | PCR–RFLP | PB | 90/60 | Yes | 7 | 24 | 63 | 3 | 12 | 42 | 6 | 16–60 | 18–69 | 2013 |
Banescu et al. [24] | Caucasian (Romania) | PCR–RFLP | PB | 78/121 | Yes | 7 | 36 | 30 | 12 | 85 | 27 | 9 | 51.76 ± 17.1 | 58.84 ± 12.9 | 2013 |
Smolkova et al. [27] | Caucasian (Germany) | TaqMan | PB | 459/549 | Yes | 9 | 178 | 216 | 65 | 216 | 256 | 77 | 6.9 ± .4.4 | 32 ± 8.1 | 2014 |
Banescu et al. [26] | Caucasian (Romania) | PCR–RFLP | PB | 78/121 | Yes | 7 | 64 | 70 | 22 | 85 | 79 | 16 | 51.5 ± 1.1 | 49.8 ± 2.1 | 2014 |
Miao et al. [28] | Asian (China) | TaqMan | PB | 545/1034 | Yes | 9 | 470 | 45 | 3 | 902 | 130 | 1 | 46 (8–80) | 43 (8–85) | 2015 |
Mutlu et al. [29] | Caucasian (Turkey) | PCR–RFLP | HB | 25/30 | Yes | 7 | 9 | 12 | 4 | 13 | 11 | 6 | NR | NR | 2015 |
Pei et al. [30] | Asian (Taiwan) | PCR–RFLP | PB | 266/266 | Yes | 7 | 214 | 39 | 13 | 241 | 19 | 6 | 7.0 ± 4.4 | 8.3 ± 4.8 | 2018 |