Objective: Juvenile idiopathic arthritis (JIA) is generally considered to be caused by interaction of genetic and environmental factors. We investigated the association of a C-to-T transition in the promoter region of the CD14 gene on chromosome 5q31.1 and JIA in a Chinese Han population.
Methods: One hundred sixty-three children with JIA and 281 healthy children (age- and sex-matched to JIA group) were studied. Polymerase chain reaction-restriction fragment-length polymorphism (PCR-RFLP) was used for analysis of the genotypes. (Trial registration number ChiCTR-CCC-00000312.)
Results: CD14 promoter-159 genotype frequencies of CC, CT, and TT were 11.48%, 49.18%, and 39.34%, respectively, in the systemic onset JIA group; 21.62%, 43.24%, and 35.14%, in the polyarticular JIA group; 16.67%, 50%, and 33.33%, in the oligoarticular JIA group; 6.9%, 75.86%, and 17.24%, in the group with other types of JIA; and 37.01%, 46.98%, and 16.01%, in the control group. Genotype frequency and allele frequency distribution were in accord with Hardy-Weinberg equilibrium. There were statistically significant differences in frequencies of genotype and allele in CD14 C-159T polymorphism between JIA group and control group (genotype: chi-squared = 33.168, p < 0.05, CT vs CC, OR 2.946, 95% CI 1.739-4.990; TT vs CC, OR 5.426, 95% CI 2.977-9.891. Allele: chi-squared = 33.168, p < 0.05, T vs C, OR 2.251, 95% CI 1.704-2.973). The T allele frequencies of boys and girls were significantly higher than those in the control group (p < 0.001 of both).
Conclusion: CD14 gene promoter C-159T polymorphism is significantly correlated with JIA in the Chinese Han population. The T allele of the C-159T polymorphism of CD14 gene may be a genetic risk factor for JIA.