A Study of Genetic Markers in Patients of Rheumatoid Arthritis and their Co-Relation with Severity of the Disease.

Introduction: Dyslipidemia has been reported to attribute to early death due to increased atherosclerosis leading to CVDs in patients with RA. Recent reports have suggested a role of adipocytokines in mediating joint damage rheumatoid arthritis (RA). RA has long been associated with increased cardiovascular risk as atherosclerosis is more prevalent in patients of RA than in the general population. Specific alleles of APOE gene have been reported to be associated with risk for atherosclerosis and LEP gene alleles have been associated with increased BMI. We evaluated the association of polymorphisms in the APOE and the LEP gene, with risk for developing RA and severity of joint damage in patients with RA.

Material & Methods: Peripheral blood samples from age and ethnicity matched healthy controls and RA patients, recruited for the study, were collected and used for DNA isolation and allele typing for D7S1875 (LEP gene) and APOE using PCR-LP/RFLP based method reported in literature4,5 followed by data analysis using Medcalc.

Results and Conclusions: Based on the findings of this study no correlation was seen between RA and LEP gene (D7S1875) allele/genotypes. It was seen that the APOE*4 allele was more prevalent in controls than in cases indicating that this allele is probably playing a significant protective role (p=0.0002, OR=0.3336, CI:0.1856-0.5997) as opposed to the other two Apo E alleles. The Apo E*3 allele was the most prevalent allele in both cases and controls which is similar to earlier reports from several different groups. No significant association was observed between the APOE genotype and the DAS28 score. Finally, it can be concluded that while the short allele of the D7S1875 (LEP gene) marker increases the risk for developing RA (OR=1.72, p=0.038) the APOE*4 allele seems to play a protective role in RA (OR=0.3336, p=0.0002).