TABLE 1.
Characteristics of case–control studies on BDNF rs6265 G > A polymorphisms and PTSD risk in system review
| First author | Year | Country/Ethnicity | Control design | Genotyping method | Case | Control | Genotype distribution | p for HWE | Traumatic factors | Age distribution | Diagnostic criteria | |||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Case | Control | |||||||||||||||
| GG | GA | AA | GG | GA | AA | |||||||||||
| Zhang | 2006 | US/Caucasian | HC | PCR‐RFLP | 96 | 250 | 69 | 26 | 1 | 166 | 92 | 8 | 0.26 | NA | Adult | DSM‐III |
| Lee | 2006 | Korea/Asian | HC | PCR‐RFLP | 107 | 161 | 28 | 57 | 22 | 48 | 82 | 31 | 0.70 | NA | Adult | DSM‐IV |
| Valente | 2011 | Brazil/Mixed | HC + PTSD− | Real‐time PCR | 65 | 767 | 48 | 15 | 2 | 584 | 169 | 14 | 0.66 | Urban violence | Adult | DSM‐IV |
| Lyoo | 2011 | Korea/Asian | HC | PRISM SnaPShot | 30 | 36 | 10 | 15 | 5 | 14 | 18 | 4 | 0.62 | Terroristattacks ‐fire | Adult | DSM‐IV |
| Pivac | 2012 | Croatia/Caucasian | PTSD− | TaqMan | 370 | 206 | 234 | 124 | 12 | 140 | 63 | 3 | 0.17 | Combat | Adult | DSM‐IV |
| Zhang | 2014 | US/Mixed | PTSD− | TaqMan | 42 | 419 | 20 | 16 | 6 | 294 | 104 | 21 | <0.01 | Combat | Adult | NA |
| Li | 2016 | China/Asian | PTSD− | PCR‐RFLP | 161 | 363 | 39 | 80 | 42 | 102 | 190 | 71 | 0.30 | Earthquake | Adolescents | PCL‐C |
| Dretsch | 2016 | US/Mixed | PTSD− | PCR‐RFLP | 41 | 185 | 28 | 8 | 5 | 129 | 49 | 7 | 0.39 | Combat | Adult | PCL‐M |
| Bruenig | 2016 | Australia/Caucasian | PTSD− | Illumina | 151 | 106 | 99 | 46 | 6 | 71 | 28 | 7 | 0.08 | Combat | Adult | DSM V |
| Dai | 2017 | China/Asian | PTSD− | Sequenom MassARRAY iPLEX platform | 28 | 167 | 2 | 26a | 38 | 109a | NA | Flood | Adult | PCL‐C | ||
| Guo−1 | 2018 | China/Asian | HC | sequenced by Sangon Biotech | 300 | 150 | 94 | 119 | 87 | 45 | 52 | 53 | <0.01 | NA | Adult | DSM‐IV |
| Young | 2018 | US/Caucasian | PTSD− | Sequencer | 58 | 168 | 36 | 22a | 113 | 55a | NA | Combat | Adult | DSM‐IV | ||
| Jin | 2019 | Korea/Asian | HC | TaqMan | 83 | 133 | 31 | 52a | 36 | 97a | NA | Mixed | Adult | DSM V | ||
| Guo−2 | 2019 | China/Asian | HC + PTSD− | PCR‐RFLP | 102 | 298 | 14 | 59 | 29 | 88 | 143 | 67 | 0.54 | Disease | Adult | DSM‐IV |
| Qi | 2020 | China/Asian | PTSD− |
Ligase Detection technique |
55 | 155 | 17 | 27 | 11 | 38 | 83 | 34 | 0.37 | Lost Children | Adult | DSM‐IV |
| Hori | 2020 | Japan/Asian | HC | TaqMan | 50 | 70 | 17 | 23 | 10 | 25 | 36 | 9 | 0.48 | NA | Adult | PDS |
Abbreviations: A, GA + AA genotype; DSM, Diagnostic and Statistical Manual of Mental Disorders; HC, Healthy control; HWE, Hardy–Weinberg equilibrium; MAF, Minor allele frequency in control group; NA, Not available; PCL‐C, PTSD Checklist Civilian Version; PCR‐RFLP, Polymerase chain reaction‐restriction fragment length polymorphism; PDS, Post‐traumatic Diagnostic Scale; PTSD, Post‐traumatic stress disorder; PTSD−, traumatic expose without PTSD symptom.