Abstract:
Background: Preceding studies have shown positive association of TNF- α
polymorphism has been found in Caucasian population for RA. Similarly studies have
been done to find association in inflammatory bowel disease in Caucasian population and
osteoarthritis in Chinese population which has come up to be negative. Age related loss
in methylation pattern has been observed in TNF promoter region while other studies
have shown varied methylation pattern of genes including DR3, IL6, IL10 in rheumatoid
arthritis.
Methods: In this study, two polymorphisms (rs361525 and rs1800750) of TNFα located
in the promoter region were studied in Pakistani population as case-control study through
restriction fragment length-polymerase chain reaction (RFLP-PCR). Methylation status
of TNF-α promoter was also investigated using Methylation specific and Un-methylation
specific PCR after bisulfite conversion of genomic DNA.
Results: The results showed that TNFα SNP rs361525 genotype had no association with
disease susceptibility while significant association was found in the SNP rs1800750, the
allele A was found to have a protective role in disease. Results showed statistically
significant association of methylation status of the promoter to RA. Additional studies
with larger and diverse populations are required to confirm current findings.
