Department of Cell Biology, University Federal of Paraná, Curitiba, PR, Brazil.
Department of Orthopedics and Traumatology, University of São Paulo, São Paulo, SP, Brazil.
Gene. 2014 Sep 1;547(2):334-7. doi: 10.1016/j.gene.2014.07.001. Epub 2014 Jul 1.
Posterior tibial tendon (PTT) is particularly vulnerable and its insufficiency is recognized as the main cause of adult acquired flatfoot. Some patients have a predisposition without clinically recognized cause, suggesting that individual characteristics play an important role in tendinopathy. The objective of the present study is to investigate the association of -519 (rs1144393) matrix metalloproteinase-1 (MMP-1) polymorphism and the -1607 (rs1799750) and -519 MMP-1 haplotypes and risk of PTT dysfunction.
The test group included 50 females who presented PTT dysfunction Grade 2 or 3, and who were submitted to surgical treatment, with histopathological examination of the tendon and magnetic resonance image (MRI) confirming tendinopathy, while the control group was 100 asymptomatic women who present intact PTT at MRI. We analyzed functional polymorphisms MMP-1 and their haplotypes using polymerase chain reaction and restriction fragment length analysis.
There was a significant difference in the presence of the different alleles and genotypes between the control group and test group for the MMP-1 gene (p≤0.01). The G allele of the -519 MMP-1 polymorphism increased susceptibility to degeneration in the PTT tendon and seems to be a genetic risk factor. Global haplotype analysis indicated a significant difference between both groups (p<0.0001). Haplotypes G-2G and A-2G had statistically significant risk effect on PTT insufficiency. G-2G, p<0.001; OR=5.72 (CI, 2.84-11.52) and A-2G p=0.002, OR=3.95 (CI, 1.65-9.44).
According to our results, -519 MMP-1 isolated and -1607/-519 MMP-1 haplotypes are associated to tendinopathy in posterior tibial tendon.
后胫肌腱（PTT）特别脆弱，其功能不全被认为是成人获得性平足的主要原因。一些患者存在无临床公认病因的易感性，这表明个体特征在肌腱病中起着重要作用。本研究的目的是探讨基质金属蛋白酶-1（MMP-1）-519 （rs1144393）多态性与-1607（rs1799750）和-519 MMP-1 单倍型及 PTT 功能障碍风险的关系。
实验组包括 50 名女性，其 PTT 功能障碍为 2 或 3 级，经手术治疗，肌腱组织病理学检查和磁共振成像（MRI）证实肌腱病，对照组为 100 名无症状女性，MRI 显示 PTT 完整。我们使用聚合酶链反应和限制性片段长度分析方法分析 MMP-1 基因的功能多态性及其单倍型。
MMP-1 基因在对照组和实验组中不同等位基因和基因型的存在存在显著差异（p≤0.01）。-519 MMP-1 多态性的 G 等位基因增加了 PTT 肌腱变性的易感性，似乎是遗传危险因素。总体单倍型分析表明两组之间存在显著差异（p<0.0001）。G-2G 和 A-2G 两种单倍型对 PTT 不足有统计学显著的风险效应。G-2G，p<0.001；OR=5.72（CI，2.84-11.52）和 A-2G p=0.002，OR=3.95（CI，1.65-9.44）。
根据我们的结果，-519 MMP-1 分离和-1607/-519 MMP-1 单倍型与后胫肌腱病有关。
