A SNP in the 5'UTR of GDF5 is associated with susceptibility to symptomatic lumbar disc herniation in the Chinese Han population

The aim of the present study is to assess whether the single nucleotide polymorphism in the GDF5 (+104T/C; rs143383) is associated with the symptomatic lumbar disc herniation in the Chinese Han population and the identification of the mechanisms of its action. This study consisted of 231 patients with symptomatic lumbar disc herniation as the case group and 370 patients who had a lifetime lack of symptoms as the control group. PCR products were genotyped. Thirty-eight disc specimens derived from the cases were analyzed by immunohistochemical staining. The stain intensity of immunohistochemistry was quantified using a computerized image analysis system. Significant differences in genotypic and allelic frequencies were found between case group and control group (TT genotype P < 0.001; CC genotype P = 0.002; T allele P < 0.001). The T allele was more frequent in the case group regardless of gender (Female P = 0.018; Male P < 0.001). Significant differences were found in the genotype frequencies when stratified by gender except the comparison between the CC genotype and other genotypes combined among the female samples (P > 0.05). A semi-quantification of collagen protein in the nucleus pulposus showed that the average collagen protein content in TC group was higher than in TT group (P < 0.05). Our results suggested that the GDF5 polymorphism is associated with a susceptibility to symptomatic lumbar disc herniation in the Chinese Han population and type II collagen in the nucleus pulposus may be a key factor in susceptibility to symptomatic lumbar disc herniation.