Table 1. Relevant studies investigating the relationship between MMP-1-1607 (rs1799750) 1G/2G polymorphisms and OA.

Author	Year	Country	Ethnicity	Type of disease	Study design	Sample size of case/control	Genotyping methods	HWE among controls	Results
Luo et al.	2015	China	Asian	TMJ OA	Case–control	206/185	PCR-RFLP	0.58	*
Lepetsos	2014	Greece	Caucasian	Knee OA	Case–control	155/139	PCR-RFLP	0.06	NO
Yang et al.	2015	China	Asian	Knee OA	Case–control	207/207	PCR-RFLP	0.97	NO
Abd-Allah et al.	2012	Egypt	Caucasian	Mixed	Case–control	100/100	PCR-RFLP	0.63	*
Barlas et al.	2008	Turkey	Caucasian	Knee OA	Case–control	157/84	PCR-RFLP	0.34	*
Rui et al.	2018	China	Asian	Knee OA	Case–control	308/404	PCR-RFLP	0.4	*

^*A significant relevance between the MMP-1 polymorphism and risk of OA was picked up in this article. Abbreviations: PCR-RFLP, PCR-restriction fragment length polymorphism; TMJ OA, temporomandibular joint OA.