Degenerated intervertebral disc prolapse and its association of collagen I alpha 1 Spl gene polymorphism: A preliminary case control study of Indian population

Background Degenerated disc disease (DDD) is a common disorder responsible for increased morbidity in a productive age group. Its etiology is multifactorial and genetic factors have been predominantly implicated. Disc prolapse results due to tear in the annulus, which is a fibrous structure composed largely of type I collagen. Functional polymorphism at the Sp1 site of the collagen I alpha 1 (COL1A1) gene has shown a positive association with DDD in Dutch and Greek populations. The purpose of this study was to assess COL1A1 Sp1 gene polymorphism in the Indian population. Materials and Methods Fifty clinically and radiologically proven patients with disc prolapse requiring surgery were included as cases and 50 healthy, age–matched volunteers served as controls. After isolating DNA from their blood sample, genotyping for COL1A1 polymorphism (rs1800012) was performed and identified as GG, GT, and TT. Results The mean age and body mass index in cases and controls were similar. 76% of the patients were males. The most common site of disc degeneration was L4–L5 (36%), followed by L5–S1 (34%). Homozygous–GG, heterozygous GT, and homozygous TT genotypes were seen in 38 (76%), 10 (20%) and 2 (4%) cases respectively, controls had similar percentage of genotypes as well. The alleles in cases and the control group showed no significant difference ( P = 0.6744) and followed the Hardy–Weinberg Equilibrium in the study population. Conclusion The COL1A1 (rs1800012) is in Hardy–Weinberg equilibrium in the present subset of Indian population. But taken as a single factor, it was not found to be associated with DDD in this preliminary study. Disc degeneration is multifactorial and also anticipated to be a result of multiple genes involvement and gene–gene interaction.