Association of PDCD1 polymorphism to Systemic Lupus Erythematosus and Rheumatoid Arthritis susceptibility

Effects of the programmed cell death 1 (PDCD1) polymorphisms in susceptibility to systemic lupus erythematosus

The failure of immunological tolerance to self-antigens plays a fundamental role in the pathogenesis of systemic lupus erythematosus (SLE). PD-1 is an inhibitory receptor for regulating the immune system and preventing development of autoimmune disorders. This study aimed to determine the role of four single-nucleotide polymorphisms (SNPs) within programmed cell death 1 (PDCD1 or PD-1) gene and haplotypes defined by these SNPs in susceptibility to SLE in the Iranian population. Blood samples were obtained from 253 SLE and 564 healthy subjects. Red blood cells were lysed and genomic DNAs were extracted using salting-out method. Genotype determinations of PD1.1, PD1.3, PD1.5 and PD1.9 SNPs were performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), and 12 haplotypes were constructed by PDCD1 SNPs. Our results showed significant differences in PD1.5 genotype frequencies between patient and control groups (p < .001). The frequencies of PD1.5 C/C, C/T and T/T genotypes versus other genotypes in SLE patients significantly differed from healthy subjects (p < .001, p = .001 and p = .002, respectively). Allelic analysis indicated a significant association between the frequency of PD1.5C allele and development of SLE in our population (odds ratio [OR] = 1.91, 95% confidence interval [CI] = 1.51-2.42, p < .001). At the haplotype level, GGCC, GACT and GGCT haplotypes were significantly different between SLE and control groups (OR = 2.14, 95% CI = 1.73-2.66, p < .001; OR = 9.76, 95% CI = 4.47-21.3, p < .001; and OR = 0.32, 95% CI = 0.24-0.42, p < .001, respectively). Based on these findings, PD1.5 SNP and some haplotypes of PDCD1 contribute to SLE risk in the Iranian population.

Programmed cell death 1 gene polymorphism as a possible risk for systemic lupus erythematosus in Egyptian females

Systemic lupus erythematosus (SLE) is a multisystem autoimmune disease with a suggested genetic basis. The newly identified human programmed cell death 1 gene could be associated with SLE susceptibility. We aimed to investigate the association between programmed cell death 1 polymorphism (PD1.3G/A (rs11568821) and PD1.5C/T (rs2227981)) with the risk of SLE in the Egyptian female population. This retrospective case-control study included 150 Egyptian females; 70 patients diagnosed to have SLE and 80 age-matched healthy controls. The two single nucleotide polymorphisms of the pdcd1 gene were genotyped by allelic discrimination through TaqMan real-time polymerase chain reaction. The PD1.3GG genotype and G allele as well as the PD1.5CC genotype were significantly more frequent in SLE patients (67.1%; p = 0.023, 82.1%; p = 0.0021, 62.9%; p = 0.0287 respectively). The GC haplotype was the most common haplotype among SLE patients (70.77%) with a reported significant linkage disequilibrium between the two studied polymorphisms (p = 0.0041). Although most of the studies showed significant association of SLE with the minor alleles, we reported a significant association between the dominant genotypes (PD1.3GG and PD1.5CC) as well as the major G allele with the risk of SLE among Egyptian females.

Are programmed cell death 1 gene polymorphisms correlated with susceptibility to rheumatoid arthritis?: A meta-analysis

BACKGROUND

Several studies investigated the relationship between programmed cell death 1 (PDCD1) gene polymorphisms and rheumatoid arthritis (RA) risk, but the results were controversial. To explore whether PDCD1 gene polymorphisms have an effect on RA risk, we conducted this meta-analysis to investigate the relationships between PDCD1 polymorphisms (rs36084323 [PD-1.1 G/A], rs11568821 [PD-1.3 G/A] and rs2227981 [PD-1.5 C/T]) and RA risk under 4 genetic models.

METHODS

PubMed, EMBASE, Web of Science, Cochrane Library China National Knowledge Infrastructure (CNKI), and Chinese Biomedical Literature Database (CBLM) were systematically searched for all eligible case-control studies. The last search was updated on September 10, 2016. Studies were accessed using Newcastle-Ottawa Scale case control study (NOS), and the combined effect size was calculated using STATA software, version 12.0. The pooled odds ratio (OR) with 95% confidence interval (CI) was calculated to assess the association. Heterogeneity analysis and subgroup analysis were also performed. Sensitivity analysis and publication bias were also performed if necessary.

RESULTS

This meta-analysis included 6 studies. The result demonstrated null association between rs36084323 (PD-1.1 G/A) polymorphism and RA susceptibility in all 4 genetic models. With regard to rs11568821 (PD-1.3 G/A), statistically significant association with RA risk was observed under allele model in Caucasians (allele model A vs G, OR = 1.19, 95% CI = 1.03-1.41). There was no significant association between rs2227981 (PD-1.5 C/T) polymorphism and RA risk.

CONCLUSION

The present study suggests that mutant A allele in rs11568821 (PD-1.3 G/A) might increase the susceptibility to RA in Caucasians.