Background: Systemic sclerosis (SSc) is a rheumatologic disease and fibroblasts are the main cells responsible for SSc pathogenesis. BIRC5 gene encodes survivin, an inhibitor of apoptosis protein. Studies suggested a role for survivin overexpression leading to decreased apoptosis of fibroblasts in SSc patients. In this study, we aimed to explore the frequencies of two SNPs in the BIRC5 gene, the rs9904341 (G>C) and rs17878467 (C>T) in SSc patients, and evaluate the gene expression of Survivin in the patients' PBMCs compared to healthy individuals.
Method and participants: We assessed the allelic and genotypic frequencies of rs9904341 in 459 SSc patients and 488 healthy controls. For the rs17878467 SNP, we analyzed the Survivin gene in 214 SSc patients and 246 controls. The genomic analyses were carried out over DNA samples isolated from PBMCs by the phenol-chloroform method. We used TaqMan rt-PCR to investigate the Survivin gene alleles. Also, we investigated the Survivin gene expression in 53 patients (lSSc = 25, dSSc =28) and 55 controls. The gene expression was assessed by specific primers for the Survivin gene (SYBR Green Real-time PCR method).
Results: The allelic and genotypic frequencies of both SNPs showed no significant difference in patients and controls. However, the Survivin expression level was significantly lower in limited SSc (lSSc), and total SSc patients in comparison to controls.
Conclusion: Our results suggested the survivin might have a role in the pathogenesis of SSc. However, more researches are needed to confirm the relationship.