MMP9 polymorphism is associated with susceptibility to non-traumatic osteonecrosis of femoral head in a Chinese Han population

// Yuan Liu 1, 2, * , Yanfei Jia 2, * , Yuju Cao 3 , Yan Zhao 2 , Jieli Du 1, 2 , Feimeng An 1, 2 , Yuxin Qi 1, 2 , Xue Feng 4 , Tianbo Jin 5 , Jianping Shi 6 and Jianzhong Wang 2 1 Inner Mongolia Medical University, Hohhot, Inner Mongolia, China 2 Department of Orthopedics and Traumatology, The Second Affiliated Hospital of Inner Mongolia University, Hohhot, Inner Mongolia, China 3 Zhengzhou Traditional Chinese Medicine Traumatology Hospital, Zhengzhou, Henan, China 4 College of Life Sciences, Inner Mongolia University, Hohhot, Inner Mongolia, China 5 The College of Life Sciences Northwest University, Xi'an, Shaanxi, China 6 Department of TCM Diagnoses, Inner Mongolia Medical University, Hohhot, Inner Mongolia, China * These authors have contributed equally to this work and should be considered co-first authors Correspondence to: Jianping Shi, email: sjp4321@126.com Jianzhong Wang, email: wangjianzhongWJ@163.com Keywords: MMP9, MMP2, non-traumatic osteonecrosis of the femoral head, single nucleotide polymorphisms, association study Received: February 28, 2017      Accepted: June 30, 2017      Published: August 24, 2017 ABSTRACT Non-traumatic osteonecrosis of femoral head (ONFH) is an orthopedic refractory disease with escalating morbidity in Chinese Han population. In our case-control study, we examined eight previously identified MMP9 single-nucleotide polymorphisms (SNPs) in 585 non-traumatic ONFH patients and 507 healthy individuals from northern China to determine whether these SNPs associated with the risk of developing non-traumatic ONFH. Genetic model and haplotype analyses were used to evaluate the association between SNPs and non-traumatic ONFH. MMP9 rs2274755 (OR, 0.740; 95% CI, 0.578-0.949; p = 0.017) was associated with a reduced risk of non-traumatic ONFH. After adjusting for age and gender, the logistic regression results showed that rs2274755 associated with a lower risk of non-traumatic ONFH in the dominant (OR=0.71, 95% CI: 0.54-0.94, p=0.016), overdominant (OR=0.73, 95% CI: 0.55-0.96, p=0.026) and log-additive (OR=0.74740; 95% CI, 0.578-0.949; p=0.017) models. In addition, the “TGC” haplotype of rs2274755 was associated with a 0.79-fold decrease in risk while the “CTC” haplotype associated with a 0.65-fold decrease risk of the non-traumatic ONFH. These results provide evidence that the MMP9 SNP at the rs2274755 locus is associated with a decreased risk of non-traumatic ONFH in a Chinese Han population.