Identification of sequence polymorphisms in themitochondrial deoxyribonucleic acid displacement-loop region asrisk factors for systemic lupus erythematosus

Abstract

Objectives: This study aims to evaluate the relationship between sequence polymorphisms (SNPs) in the displacement-loop (D-loop) region ofmitochondrial deoxyribonucleic acid (mtDNA) and systemic lupus erythematosus (SLE) in Chinese female patients. Patients and methods: This cross-sectional study was conducted between May 2017 and October 2017. The mtDNA was extracted from theperipheral blood of 97 female SLE patients (mean age 40.8 years; range, 20 to 79 years) and 108 age-matched healthy controls (mean age 48.7years; range, 22 to 78 years). The SNPs of mtDNA D-loop were verified by polymerase chain reaction amplification and sequence analysis. The allelefrequencies of D-loop region were compared by the Chi-square test between SLE and control groups. Results: The SNP accumulation in SLE patients was significantly higher than that in the controls (p=0.027, 95% confidence interval [CI]: 0.075, 1.210).The frequencies of the major alleles of the nucleotides 73G/A (p