[Association of interleukin-6 and interleukin-18 gene polymorphism with rheumatoid arthritis in Guangdong Han population].
OBJECTIVE
To investigate the single-nucleotide polymorphisms (SNPs) at positions -572 and -174 in the promoter region of interleukin-6 (IL-6) gene and at -607 and -137 in the promoter region of interleukin-18 (IL-18) gene for their association with rheumatoid arthritis (RA) in the Chinese Han population in Guangdong Province.


METHODS
SNPs of IL-6 and IL-18 genes were detected in 120 patients with RA and 168 normal subjects using polymerase chain reaction with sequence-specific primers (PCR-SSP).


RESULTS
SNPs at -572 and -174 of IL-6 gene and at -607 and -137 of IL-18 gene were detected in this population. There was a significant difference in the genotype and allele frequency at -572 and -174 of IL-6 gene and -607 of IL-18 gene (P<0.001), but not in the distribution of genotype frequencies at -137 of IL-18 gene between the RA patients and healthy subjects (P=0.141). A significant difference was found, however, in the allele frequency at -137 of IL-18 (P=0.024). Logistic regression analysis revealed significant association of age, gender, IL-6 gene -572, -174 and IL-18 gene -137 SNPs with RA (P<0.05).


CONCLUSIONS
The polymorphisms of the promoter region of IL-6 gene at positions -572 and -174 is probably associated with RA, and further study is needed to understand the relation of the polymorphisms of IL-18 gene at positions -607C/A and-137G/C with RA.
Huang
Xian-zhang
XZ
Clinical Laboratory, Ershadao Branch, Guangdong Provincial Hospital of Traditional Chinese Medicine, Guangzhou 510105, China. xianzhanghuang@yahoo.com.cn
Zhuang
Jun-hua
JH
Ren
Yan-ge
YG
Zhou
Luo-jing
LJ
Zhou
Qiang
Q
D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001172:Arthritis, Rheumatoid / Q000235:genetics*; D044466:Asian People / Q000235:genetics; D016022:Case-Control Studies; D002681:China; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D020382:Interleukin-18 / Q000235:genetics*; D015850:Interleukin-6 / Q000235:genetics*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D011401:Promoter Regions, Genetic; D055815:Young Adult
C508600:IL6 protein, human; D020382:Interleukin-18; D015850:Interleukin-6