Evaluation of Fas Promoter Gene Polymorphism in Patients with Systemic Lupus Erythematosus

Choi, Seong Jae; Kim, Ye Ree; Lee, Young Ho; Ji, Jong Dae; Song, Gwan Gyu

Abstract

OBJECTIVE
To investigate whether the polymorphism of Fas promoter gene is associated with susceptibility to systemic lupus erythematosus (SLE) and its clinical features.
METHODS
Polymerase chain reaction of genomic DNA-restriction fragment length polymorphism using MvaI was used to determine genotypes of the Fas promoter in 87 SLE patients and 87 healthy control subjects. Clinical manifestations were analyzed in each patient and correlated with the genotypes.
RESULTS
The genotype distribution of the Fas promoter did not differ between SLE patients and control subjects (AA, GA, GG genotypes 31.0%, 54.0%, 14.9% in SLE patients vs. 29.9%, 55.2%, 14.9% in controls respectively, chi2=0.03, 2 degrees of freedom, p=0.99). No significant differences were also found in allele frequencies between the groups. Clinically in the lupus patients according to the Fas promoter polymorphism, there were no significant differences in age at onset, anti-ds DNA titer, C3, C4 level, renal involvement, number of ACR (American College of Rheumatology) criteria presented, SLE Disease Activity Index, SLICC/ACR (The Systemic Lupus international Collaborating Clinics/American College of Rheumatology) damage index, and autoantibody profiles except for anti-RNP antibody. The frequency of anti-RNP antibody in the lupus patients was increased in AA group (71.4%) compared to GA and GG groups (26.2% and 30.0%, p=0.007).
CONCLUSION
The Fas promoter polymorphism does not seem to confer susceptibility to SLE, but seems to have some influence on the development of certain autoantibody like anti-RNP antibody, suggesting that the Fas promoter polymorphism is functional.