Objective: The objective of this study was to confirm whether polymorphisms of the poly(ADP-ribose) polymerase gene (PARP) are associated with genetic susceptibility to systemic lupus erythematosus (SLE) and to investigate the possible association of nephritis and arthritis in SLE with PARP polymorphisms.
Methods: Using direct DNA sequencing in 24 individuals, we identified 44 sequence variants within exons and their flanking regions, including the 1.5-kb promoter region of PARP. Six common polymorphic sites were selected for larger-scale genotyping (in 350 Korean SLE patients and 330 healthy controls), which identified six common haplotypes.
Results: Although no statistically significant association with the risk of SLE was observed, we found that two single-nucleotide polymorphisms (SNPs -1963A --> G and +28077G --> A) were significantly associated with an increased risk of nephritis, and one non-synonymous variant [+40329T --> C(V762A)] was also significantly associated with an increased risk of arthritis, while the -1963A --> G SNP showed a protective effect on arthritis in Korean SLE patients.
Conclusion: Our results demonstrate that PARP polymorphisms are not associated with SLE susceptibility, but that -1963A --> G, +28077G --> A and +40329T --> C(V762A) are significantly associated with nephritis and arthritis in Korean SLE patients.