Association of BCL-2 polymorphism with the presence and severity of lumbar disc degeneration in the Chinese Han population.

ABSTRACT

BACKGROUND: Apoptosis is involved in the mechanism of lumbar disc disease (LDD). BCL-2 has been shown to play an anti-apoptosis role. The present study aims to examine the association of -938C > A polymorphism of the BCL-2 gene with the presence and severity of LDD in the Chinese Han population. METHODS: This study consisted of 325 patients with LDD and 236 normal controls. The grade of disc degeneration was determined according to Schneiderman's classification for MRI. -938C > A polymorphism was determined by "slow-down" polymerase chain reaction (PCR) method. RESULTS: The genotype frequency of -938C > A polymorphism was consistent with Hardy-Weinberg equilibrium (p = 0.136). Higher frequencies of -938CA and AA genotypes were found in patients with LDD compared with normal controls (p = 0.019). Furthermore, there were higher frequencies of the A allele in LDD patients than in normal controls (p = 0.005). Unconditional logistic regression analysis revealed that -938CA and AA genotypes were significantly associated with the presence of LDD compared with CC genotype (p = 0.041; OR 1.449; 95% CI 1.015 - 2.067 and p = 0.015; OR 2.102; 95% CI 1.158 - 3.813, respectively). The A allele was significantly associated with the susceptibility to LDD compared with the C allele (p = 0.005; OR 1.436; 95% CI 1.113 - 1.851). In addition, -938CA and AA genotypes, as well as the A allele were found to be associated with the risk for higher degenerative grades of LDD compared with the CC genotype and C allele, respectively (p = 0.017 and p = 0.003, respectively). CONCLUSIONS: The -938C > A polymorphism of BCL-2 may be associated with the presence and severity of LDD in the Chinese Han population.