Role of APOE and IL18RAP gene polymorphisms in cervical spondylotic myelopathy in Indian population

Cervical spondylotic myelopathy (CSM) is a progressive degenerative spine disease. It is not clear why certain patients develop symptomatic myelopathy whereas others do not, even in the presence of radiographic features of cervical stenosis. Genetic predisposition has been suggested, supported by familial occurrence of CSM. In this study we explored the demographic and radiographic features of CSM in Indian population and studied the association between polymorphisms in interleukin18RAP and apo-lipoprotein genes in CSM. A total of 100 CSM patients and 100 healthy control subjects were included in this study. Genotyping of APOE (rs7412 and rs429358) and IL18RAP (rs1420106 and rs917997) gene polymorphisms was performed by Taqman allelic discrimination assay. Comparison of allelic frequencies, ε2 versus ε3 (OR = 4.4, 95%CI = 1.23-15.73, P = 0.002) and ε2 versus ε4 (OR = 6.67, 95%CI = 1.58-28.04, P = 0.009) showed a statistically significant association for the risk of CSM. There was no significant association between different genotypes with sex, T2 signal intensity change and Nurick grade. Only patients having multiple level cervical prolapsed intervertebral disc (PIVD) on MRI, had a higher proportion of the ε2 allele as compared to controls (p = <0.0001). No significant association was found between IL18RAP gene polymorphisms (rs1420106 and rs917997) with the risk of CSM. ε2 allele was associated with the risk of CSM in Indian population. There was no significant association between the two single nucleotide polymorphisms (SNPs) of IL18RAP gene with risk of CSM.