Association of gene polymorphisms and the decreased expression of long non-coding RNA LOC553103 with rheumatoid arthritis

Background: Long non-coding RNAs (lncRNAs) are involved in many key bioprocesses, including the occurrence and development of rheumatoid arthritis (RA). We aimed to analyze the association of genetic variants of long non-coding RNA LOC553103 and its peripheral blood mononuclear cells (PBMC) expression with RA. Methods: We enrolled 457 RA patients and 551 healthy controls and conducted a case-control study to analyze the relationship between LOC553103 gene rs272879 and the susceptibility of RA by TaqMan single nucleotide polymorphism genotyping. Among them, we sampled 92 cases and 92 controls, respectively, to detect the PBMC level of LOC553103 using quantitative real-time polymerase chain reaction technology. We explored the association between LOC553103 rs272879 and its PBMC expression levels in 71 RA patients. Mann-Whitney, Chi-square, and Spearman correlation analysis were used for statistical analysis and P-value <.05 was considered statistically significant. Results: The genotype frequency of LOC553103 rs272879 CC was increased, and CG was decreased in RA patients compared to the control group (chi(2) = 6.772, P = .034). The LOC553103 expression level in PBMC of RA patients was downregulated compared to healthy control (Z = -4.497, P < .001). Moreover, negative correlations were observed between the PBMC level of LOC553103 and erythrocyte sedimentation rate (r(s) = -0.262, P = .018), white blood cell count (r(s) = -0.382, P = .004), platelet (r(s) = -0.293, P = .030), and disease activity score in 28 joints (r(s) = -0.271, P = .016) in RA patients. Conclusions: This study provides the first evidence supporting an association between LOC553103 gene polymorphisms and susceptibility of RA and a relationship of PBMC level of LOC553103 with clinical manifestations and laboratory indicators of RA patients.