| Author publication year country of study | Study population characteristics | Diagnosis diagnostic criteria | Gene(s) studied | Results | Study limitations |
| Planello [17] 2011 Brazil | Mean Age of Cases 42.82 ± 14.96 N = 115: F = NR, M = NR Mean Age of Controls 38.04 ± 14.17 N = 117: F = NR, M = NR Ethnic status: Brazilian | Osteophytes, erosion, avascular necrosis, subchondral cyst, loose bodies, OA CT, Interview, MRI | MMP1 MMP3 MMP9 | Only MMP1 2G/2G genotype was found to be significant (P < 0.003). Effect of age on TMJ degeneration was significant (P < 0.002) | Small sample size to detect association of MMP3 gene |
| Huang [13] 2011 Japan | Mean Age of Cases 15.5 to 69.7 N = 55: F = 44, M = 11 Mean Age of Controls NR N = NR: F = NR, M = NR Ethnic status: Japanese | TMJ clicking (disc displacement with reduction) or closed lock (disc displacement without reduction) and not having previous history of trauma, neoplasm and/or surgery in the TMJ; TMJ clicking used as controls Clinical evaluation, MRI | ANKH | Two alleles of ANKH-OR polymorphism were identified. ANKH-OR homozygotes were more likely to develop closed lock compared to controls (P = 0.011) | Calculation of minimal sample size was unattainable, Low response rate could have resulted in sampling bias, application of cohort study would have explored the influence of age on TMD, high percentage of patients were unwilling to take a blood test for assessment, study failed to indicate equivalence between fibrous ankylosis in mice and closed lock in humans |
| Kim [19] 2010 South Korea | Mean Age of Cases 31.45 ± 15.25 years N = 74: F = 50, M = 24 Mean Age of Controls 35.58 ± 12.47 N = 64: F = 41, M = 23 Ethnic Status: Korean | MPDS, IDD with reduction, IDD without reduction, OA, Osteoarthrosis RDC/TMD | ESR1 | No statistical difference between study group and control group (P > 0.5) | Small sample size |
| Ribeiro-Dasilva [18] 2009 Brazil | Age for Cases 18 - 44 N = 300: F = 300, M = 0 Age for Controls 31.1 ± 8.36 N = 100: F = 100, M = 0 Ethnic Status: White, Afro-American, Asiatic | Disc displacement with and without reduction, with limited mouth opening, without reduction and without limited mouth opening RDC/TMD | ESR1 | Presence of [GC] haplotype in ERĪ± gene was higher in TMD with pain compared to control group (P = 0.0028) | Small sample size, admixed Brazilian population limits generalizability of data, only data from articular pain included and not muscular pain |
| Matsumoto [14] 2008 Japan | Mean Age of Cases 50.11 N = 9: F = 8, M = 1 Mean Age of Controls 65.5 N = 2: F = 2, M = 0 Ethnic Status: NR | ID, OA NR | ADAMTS-5 | ADAMTS-5 is involved in deformation of the TMJ discs with ID and OA (P < 0.01) | Small sample size, limited use of TMJ disc cells |
| Helenius [21] 2004 Finland | Mean Age of Cases 43.57 N = 84: F = 56, M = 28 Mean Age of Controls: NR N = 100: F = NR, M = NR Ethnic status: Finnish | RA, MCTD, AS, SPA ARA 1987 for RA, Alarcon-Segovia for MCTD, MNYC for AS, ESSG for SPA | HLA-DRB1 | In the whole patient population, HLA-DRB1 allele was significantly associated with TMJ erosions (P = 0.0014) | Controls were not clinically or radiologically examined |