Association Between XRCC3 Thr241Met SNP and Systemic Lupus Erythematosus in Han Chinese Patients in Taiwan, and a Meta-Analysis of Healthy Populations

Background X‐ray repair cross‐complementing group 3 (XRCC3) plays a crucial role in mammalian DNA repair processes. The polymorphism of XRCC3, rs861539 (Thr > Met at codon 241), is common in populations worldwide. This study analyzed the relationship between this functional single nucleotide polymorphism and systemic lupus erythematosus (SLE) in the Han Chinese population in Taiwan (HC‐TW). Methods Genotyping was performed using polymerase chain reaction restriction fragment length polymorphism on 163 SLE patients and 191 healthy participants in the control group. Results The data showed that the genotype frequency at codon 241 did not differ significantly between the SLE patients and the healthy participants in the control group; however, the allele frequency analysis indicated a significant difference between these groups. In addition, we used the genotype and allele frequencies of 191 healthy HC‐TW participants for comparison with HapMap populations. The results indicated a significant difference of XRCC3 Thr241Met allele and genotype frequencies between the HC‐TW population and HapMap populations, except for the other Han Chinese populations. A prior study showed that Thr241 > Met substitution in XRCC3 protein was positive as damaging and functional consequences as well. Conclusion This is the first study to demonstrate the difference of XRCC3 Thr241 > Met variant between the HC‐TW population and HapMap population.