Tumor necrosis factor-α, CD1A and CD1E genetic polymorphisms in Guillain-Barre syndrome: A study from India

Background: Guillain-Barre Syndrome (GBS) is an acute acquired autoimmune inflammatory disorder of peripheral nerves and roots. The pathogenesis is essentially an aberrant post-infectious immune response in a genetically susceptible host milieu. Single nucleotide polymorphisms (SNP) in genes encoding the inflammatory mediators like TNF-a, CD1A and CD1E can influence their expression and level and the susceptibility and clinical course of disease in GBS. Objective: We tried to study the susceptibility of single nucleotide polymorphisms of TNF-a and CD1 genes in Guillain-Barre Syndrome in Indian population and determine the association in terms of genotype, allele and haplotype distribution along with individual subtype, severity and clinical outcome. Methodology: In this case-control study, we investigated the single nucleotide polymorphism pattern in the promoter region of TNF-a (-308 G/A), TNF-a (-863C/A), CD1A and CD1E genes using real-time polymerase chain reaction in 75 GBS patients and analysed in comparison with 75 age and sex-matched healthy controls. Results: The findings revealed that the allelic distribution of TNF-a (-308 G/A) *A allele was associated with GBS (P value 0.04, Odds Ratio 2.03, 95% Confidence Interval 1.01-4.07). There was no association found with genotype, haplotype combination and other allele distribution for GBS in the study. CD1A and CD1E SNPs did not reveal any susceptibility for GBS. The subtype analysis did not reveal any statistical significance, except for CD1A *G allele with AMAN subtype (P value 0.026). The haplotypic combinations and mutant allele of TNF-a (-308 G/A), TNF-a (-863C/A), CD1A and CD1E were significantly associated with severe GBS in the study. However, there was no association of any SNP for mortality and survival of GBS in the study. Conclusion: TNF-a (-308 G/A)*A allele might confer genetic susceptibility for GBS in Indian population. CD1 genetic polymorphism could not be considered for susceptibility to GBS. TNF-a and CD1 genetic polymorphism did not affect mortality in GBS.