Table 1. Information of the included studies that investigated the relationship between TNF-α-308G>A and the risk of inflammatory bowel disease and colorectal cancer.
| First Author (Year)a | Country (Racial descent)b | Study Design | Case (−308 G>A)c | Control (−308 G>A)c | Variant allele frequency |
|---|---|---|---|---|---|
| Bouma et al14 | Netherlands (European) | Pop c/c | CD (25/10/0) | (65/29/4) | 0.189 |
| Sashio et al15 | Japan (Asian) | Pop c/c | UC (89/16/1) | (107/4/0) | 0.018 |
| CD (119/4/1) | |||||
| Martin et al16 | Germany (European) | Pop c/c | UC (74/19/0) | (87/32/0) | 0.134 |
| CD (78/17/0) | |||||
| Gonzalez et al17 | Spain (European) | Pop c/c | CD (41/9/0) | (76/21/3) | 0.135 |
| Vatay et al18 | Hungary (European) | Pop c/c | UC (41/9/0) | (93/41/4) | 0.178 |
| CD (63/11/0) | |||||
| Balding et al19 | Ireland (European) | Pop c/c | UC (78/23/7) | (233/140/16) | 0.221 |
| CD (37/26/1) | |||||
| Yamamoto-Furusho K et al20 | Mexico (European) | Pop c/c | UC (61/19/0) | (96/3/0) | 0.015 |
| Fowler et al21 | Australia (European) | Pop c/c | CD (198/91/15) | (150/61/6) | 0.168 |
| Cantor et al22 | Canada (European) | Pop c/c | UC (35/18/2) | (63/27/2) | 0.168 |
| CD (103/30/5) | |||||
| Song et al23 | China (Asian) | Pop c/c | UC (86/16/1) | (211/9/0) | 0.020 |
| CD (26/2/0) | |||||
| Ferreira et al24 | Portugal (European) | Pop c/c | CD (171/55/9) | (684/229/12) | 0.136 |
| Zipperlen et al25 | Canada (European) | Pop c/c | CD (85/41/2) | (67/33/3) | 0.189 |
| Castro-Santos et al26 | Spain (European) | Pop c/c | CD (108/31/7) | (265/71/7) | 0.124 |
| UC (70/26/3) | |||||
| Yang et al27 | Korea (Asian) | Pop c/c | CD (255/29/4) | (342/54/3) | 0.075 |
| Sykora et al28 | Zech (European) | Pop c/c | CD (38/8/0) | (71/10/1) | 0.073 |
| UC (22/12/2) | |||||
| Qian et al29 | Chinese (Asian) | Pop c/c | UC (79/30/1) | (242/48/2) | 0.089 |
| Celik et al30 | Turkey (Asian) | Pop c/c | CD (56/14/0) | (86/18/1) | 0.095 |
| UC (96/23/1) | |||||
| Cucchiara et al31 | Italy (European) | Pop c/c | UC (140/28/5) | (308/37/2) | 0.059 |
| CD (137/46/5) | |||||
| Mittal et al32 | India (European)d | Pop c/c | UC (9/79/4) | (10/147/7) | 0.490 |
| CD (3/17/2) | |||||
| Ferguson et al33 | NewZealand (European) | Pop c/c | UC (258/122/23) | (282/123/10) | 0.172 |
| CD (260/112/16) | |||||
| Jang et al34 | Korea (Asian) | Pop c/c | CRC (24/3/0) | (85/7/0) | 0.038 |
| Landi et al35 | Spain (European) | Hosp c/c | CRC (278/80/5) | (234/76/10) | 0.150 |
| Macarthur et al36 | Scotland (European) | Pop c/c | CRC (157/74/15) | (224/145/20) | 0.238 |
| Gunter et al37 | USA (European) | Pop c/c | CRC (146/59/12) | (139/57/6) | 0.170 |
| Theodoropoulos et al38 | Greece (European) | Pop c/c | CRC (152/56/14) | (146/44/10) | 0.160 |
| Toth et al39 | Hungary (European) | Pop c/c | CRC (132/48/3) | (111/30/0) | 0.106 |
| Garrity-Park et al40 | Ireland (European) | Hosp c/c | CRC (52/49/13) | (92/20/2) | 0.105 |
Abbreviations: CD, Crohn's disease; UC, Ulcerative colitis; CRC, Colorectal cancer.
a
Reference number.
b
The world population falls into three basic racial groups: Mongoloid (such as Asian), Negroid (African), and European (Caucasian or White).
c
Wild-type homozygote/heterozygote/variant homozygote.
d
It was reported that most inhabitants' ancestor of Indians are White. Although, U.S. population is highly heterogeneous, more than 70% residents are White. Thus, the population of these two countries were categorized as European.