Background and purpose: Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease of multiple and poorly understood aetiopathogenesis. Genetic factors involved in the pathogenesis of sporadic ALS still remain unknown. A candidate gene might be matrix metalloproteinase-9 gene (MMP-9) - a member of the matrix metalloproteinase family capable of degrading elements of the extracellular matrix. Recent data suggest that MMP-9 may be involved in the pathophysiology of ALS. MMP-9 levels and activity are influenced by the -1562 C/T polymorphism of the MMP-9 gene. We have studied the association between the -1562 C/T polymorphism of the MMP-9 gene and the risk of sporadic ALS.
Material and methods: We included 228 patients with a definite or probable diagnosis of sporadic ALS and 428 healthy controls matched for age and sex. The diagnosis of sporadic ALS was established according to El Escorial criteria. The polymorphism was studied by polymerase chain reaction (PCR) and restricted enzyme digestion.
Results: Distribution of genotypes and alleles of the MMP-9 gene between sporadic ALS cases and controls did not differ significantly: C/C - 168 (73.7%) vs. 304 (71.0%), C/T - 53 (23.2%) vs. 118 (27.6%), T/T - 7 (3.1%) vs. 6 (1.4%), respectively and alleles: C - 389 (85.3%) vs. 726 (84.8%), T - 67 (14.7 %) vs. 130 (15.2%), respectively.
Conclusion: The polymorphism -1562 C/T of the MMP-9 gene is not associated with the risk of sporadic amyotrophic lateral sclerosis in the studied population of Polish patients.