Preterm birth or PTB (<37 weeks) is a heterogeneous phenotype with numerous biological pathways. The lack of explanation due to complex pathways, inconsistent observations indicates the need for employing the role of genetic determinants to anticipate the danger of PTB. In this present study, we investigated the possible gene-gene interaction of five SNPs with PTB and its association with total MMP-9 levels. A total of 510 recruitments (250 terms and preterm each) were made and were genotyped by Restriction Fragment length polymorphism (RFLP). Generalized Multifactor Dimensionality Reduction (GMDR) method was carried out for determining gene-gene interaction. ANOVA and t-test were used to identify the association of IL-6 polymorphism with PTB alone and correspondingly with PTB and low birth weight infants (i.e. < 2500 kg). The combination of IL-6 and MMP-9 and MMP-1, MMP-8 and MMP-9 polymorphism was selected through GMDR analysis concerning mothers with preterm and term birth (accuracy 0.5921 and 0.8030 with Cross-Validation Consistency (CVC) 10/10 respectively). Increased expression of MMP-9 was reported in cases in those mothers carrying IL-6 G allele, which was profoundly associated with PTB independently. IL-6 polymorphisms showed synergistic effects in terms of increased total MMP-9 levels in the present study.

中文翻译：

---

IL-6：早产中 MMP-9 的内源性激活剂。

早产或 PTB（<37 周）是一种具有多种生物学途径的异质表型。由于复杂的途径缺乏解释，不一致的观察表明需要利用遗传决定因素的作用来预测 PTB 的危险。在本研究中，我们调查了五个 SNP 与 PTB 之间可能的基因-基因相互作用及其与 MMP-9 总水平的关联。总共进行了 510 次招募（每次 250 次和早产），并通过限制性片段长度多态性 (RFLP) 进行基因分型。进行了广义多因素降维（GMDR）方法来确定基因-基因相互作用。方差分析和 t 检验用于确定 IL-6 多态性与单独的 PTB 以及相应地与 PTB 和低出生体重婴儿（即 < 2500 kg）的关联。IL-6 和 MMP-9 的组合以及 MMP-1、MMP-8 和 MMP-9 多态性的组合是通过关于早产和足月母亲的 GMDR 分析选择的（准确度 0.5921 和 0.8030，交叉验证一致性（CVC）10/ 10 个）。据报道，在携带 IL-6 G 等位基因的母亲的病例中，MMP-9 的表达增加，这与 PTB 密切相关。在本研究中，IL-6 多态性在增加总 MMP-9 水平方面显示出协同作用。这与 PTB 有深刻的独立联系。在本研究中，IL-6 多态性在增加总 MMP-9 水平方面显示出协同作用。这与 PTB 有深刻的独立联系。在本研究中，IL-6 多态性在增加总 MMP-9 水平方面显示出协同作用。