Objectives: Previous studies indicate that genetic variants in genes encoding proteins like matrix metalloproteinase (MMP) enzymes may affect degeneration of the intervertebral disk. One such genetic variant is a single nucleotide polymorphism insertion in the promoter region of the MMP1 gene, that is, the MMP1 rs1799750 2G allele, which increases the MMP1 expression in vitro. In this study, we examined whether the MMP1 rs1799750 2G allele might be associated with disk degeneration and clinical outcome after lumbar disk herniation.
Materials and methods: A total of 260 patients with lumbar disk herniation and sciatic pain were included in this study and genotyped for the MMP1 rs1799750 2G allele.
Results: The present data showed no differences in the frequency of the MMP1 2G allele in patients recently diagnosed with disk herniation compared with pain-free controls. Moreover, in the patients, the MMP1 2G allele was not directly related to the disk degeneration. However, our data demonstrated that the MMP1 2G allele was associated with both pain and disability, that is, increased visual analog scale score, McGill Pain Questionnaire score, and Oswestry Disability Index score. Clearly, the patients homozygous for the 2G allele had more pain and reduced function compared with those carrying the 1G allele.
Discussions: Our findings suggest that the MMP1 rs1799750 2G/2G genotype may contribute to low back pain, sciatica, and disability after lumbar disk herniation.