Association of MMP7 T > C Gene Variant (rs10502001) and Expression in Chronic Obstructive Pulmonary Disease

Patients with chronic obstructive pulmonary disease (COPD) have obstructed airflow through their lungs. Single nucleotide polymorphisms in matrix metalloproteinases (MMPs) genes and the risk of COPD have been the subject of numerous studies, with conflicting results. This investigation was conducted to determine whether the MMP7 (T>C) gene variant (rs10502001) was associated with an increased risk of COPD. A case-control study was conducted with 360 subjects (180 healthy controls and 180 COPD cases). The polymerase chain reaction (PCR)-restriction fragment length polymorphism method was used to genotype the SNP rs1050200. mRNA expression of MMP7 was performed using RT-PCR. The genotypic/allelic frequencies and carriage rates of rs10502001 (T>C) polymorphism were evaluated in 180 each of healthy controls and COPD cases. Cases have higher TC/CC genotype frequencies than controls. The "CC" genotype was found to be significantly associated with increased COPD risk (p = 0.016). The "C" allele frequency was higher in cases than in controls and showed significant association with COPD (p = 0.005). The carriage rate frequencies of T(-) and C(+) were significantly higher in cases than in controls (p = 0.031 and 0.047, respectively). MMP7 expression was significantly upregulated (p = 0.001) in COPD cases as compared with the controls. In addition, comparisons of MMP7 expression between the COPD cases with different genotypes showed that the "CC" genotype cases had significantly higher expression than those with "TT" genotype. The present findings showed statistically significant correlation of MMP7 (T>C) polymorphism and expression with COPD. Therefore, MMP7 responsible for degradation of elastin has been strongly linked to the progression of COPD.