Table 2.
Characteristic of studies included in the meta-analysis of the association of TNF-α gene polymorphism with the risk of IS
| Study No. | First author [Ref.], year | Origin | Ethnicity | Sample size case/control, n | Stroke subtype | Variant | PCR method | Matching criteria | M/F case M/F control | Age case/control, years | HWE | Source of control | Quality score |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | Lalouschek [21], 2006 | Austria | Caucasian | 404/415 | IS | −308G/A −238G/A G376A G244A | Multiplex PCR | Age, sex | 257/147 253/162 | 53/49 | Yes | PB | 15 |
| 2 | Tuttolomondo [22], 2012 | Italy | Caucasian | 96/48 | IS | −308G/A | PCR-RFLP | Age | 45/51 16/32 | 71.9±9.75/71.4±7.45 | Yes | HB | 11 |
| 3 | Sultana [23], 2011 | India | Asian | 238/226 | IS | −308G/A | ARMS-PCR | n.a. | 164/74 121/105 | 53.72±11.11/54.06±10.98 | Yes | PB | 11 |
| 4 | Banjeree [24], 2007 | India | Asian | 112/212 | IS | −308G/A | PCR-RFLP | Age, sex | 72/40 143/69 | 58.6±14.2/57.4±8.8 | Yes | PB | 11 |
| 5 | Rubattu [25], 2004 | Italy | Caucasian | 115/180 | IS | −308G/A | PCR-RFLP | Age | 51/64 98/82 | 35.95±8.12/34.7±6.9 | Yes | HB | 9 |
| 6 | Harcos [26], 2006 | Hungary | Caucasian | 336/333 | IS | −308G/A | PCR-RFLP | n.a. | n.a. | n.a. | Yes | PB | 9 |
| 7 | Balding [27], 2004 | Ireland | Caucasian | 105/389 | IS | −308G/A | PCR-RFLP | n.a. | 63/42 226/163 | 69 (35–99)/37.1 (18–65) | No | PB | 7 |
| 8 | Lee [28], 2004 | South Korea | Asian | 152/165 | IS | −308G/A | PCR-RFLP | n.a. | 85/67 78/87 | 60.9/59.1 | No | PB | 9 |
| 9 | Um [29], 2004 | South Korea | Asian | 366/610 | IS | −308G/A | PCR-RFLP | Age, sex | 180/186 294/316 | 61.0±14.5/62.2±9.8 | Yes | HB | 11 |
| 10 | Kim [30], 2010 | South Korea | Asian | 237/216 | IS | −308G/A −238G/A | PCR-RFLP | Age, sex | 138/99 113/103 | 61.68±11.09/60.32±10.92 | Yes | PB | 11 |
| 11 | Tong [31], 2010 (1st study) | China | Asian | 648/648 | IS | −308G/A −238G/A | Taqman SNP genotyping | Age, sex | 379/269 379/269 | 61.12±9.98/60.21±9.8 | Yes | PB | 13 |
| 12 | Tong [31], 2010 (2nd study) | China | Asian | 100/100 | IS | −308G/A −238G/A | Taqman SNP genotyping | Age, sex | 58/42 58/42 | 64.12±9.36/63.18±10.19 | Yes | PB | 13 |
| 13 | Wawrzynek [32], 2014 | Poland | Caucasian | 101/100 | IS | −308G/A | Nested PCR | Age, sex | 69/32 60/40 | n.a. | No | HB | 5 |
| 14 | Llamas [33], 2007 | Spain | Caucasian | 292/302 | IS | −238G/A −308G/A | PCR | Age, sex | n.a. | 70.9±8/70.9±8 | No | PB | 11 |
| 15 | Wu [34], 2011 | China | Asian | 108/121 | IS | −238G/A | PCR | Age, sex | n.a. | n.a. | No | PB | 9 |
| 16 | Liu [35], 2009 | China | Asian | 57/103 | IS | −238G/A | PCR | Age, sex | n.a. | n.a. | No | HB | 8 |
| 17 | Cui [36], 2012 (1st study) | China | Asian | 1,388/1,027 | IS | T1031C −308G/A C857T | Taqman PCR | Ethnicity Geographical | n.a. | n.a. | Yes | PB | 10 |
| 18 | Cui [36], 2012 (2nd study) | China | Asian | 961/821 | IS | T1031C −308G/A C857T | Taqman PCR | Ethnicity Geographical | n.a. | n.a. | Yes | PB | 10 |
M = Male; F = female; PB = population based; HB = hospital based; PCR-RFLP = polymerase chain reaction-restriction fragment length polymorphism; SNP = single nucleotide polymorphism; n.a. = not applicable.