Cytokine gene polymorphisms associated with rheumatoid arthritis and periodontitis in Japanese adults.
BACKGROUND
Cytokines play a major role in the pathogenesis of rheumatoid arthritis (RA) and periodontitis. Both diseases were previously shown to be partly influenced by cytokine gene polymorphisms. Therefore, we evaluated whether the distributions of the cytokine genotypes were unique to subjects with both diseases.


METHODS
The study subjects consisted of Japanese adults with RA (RA group; n = 153), periodontitis only (P group; n = 117), and healthy individuals (H group; n = 108). Clinical periodontal condition was defined by measurements of probing depth, clinical attachment level, and bleeding on probing. Genomic DNA was isolated from peripheral blood and analyzed for the determination of 16 gene polymorphisms encoding interleukin (IL)-1, -2, -4, -6, and -10, tumor necrosis factor-alpha, and transforming growth factor-beta 1.


RESULTS
The frequency of patients with RA who exhibited periodontitis was 89.5% (RA + P group; n = 137). No significant differences were observed in any of the frequencies of cytokine genotypes and alleles among the subject groups. After adjustment for age, gender, and smoking status, multiple logistic regression analysis revealed a significant difference in the distribution of IL-1B +3954 genotypes between RA + P and P groups (P = 0.006) and between RA + P and H groups (P = 0.008).


CONCLUSIONS
Japanese individuals with RA and periodontitis may exhibit different distributions of IL-1B +3954 genotypes than healthy controls and subjects with periodontitis only.
Kobayashi
Tetsuo
T
General Dentistry and Clinical Education Unit, Niigata University Medical and Dental Hospital, Niigata, Japan. kotetsuo@dent.niigata-u.ac.jp
Murasawa
Akira
A
Ito
Satoshi
S
Yamamoto
Kouji
K
Komatsu
Yasutaka
Y
Abe
Asami
A
Sumida
Takayuki
T
Yoshie
Hiromasa
H
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000483:Alleles; D001172:Arthritis, Rheumatoid / Q000150:complications* / Q000235:genetics*; D044466:Asian People / Q000235:genetics; D016022:Case-Control Studies; D016207:Cytokines / Q000235:genetics*; D005260:Female; D005787:Gene Frequency; D006801:Humans; D007378:Interleukins / Q000235:genetics; D007564:Japan; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D010518:Periodontitis / Q000150:complications* / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide; D012307:Risk Factors; D053773:Transforming Growth Factor beta1 / Q000235:genetics; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics
D016207:Cytokines; D007378:Interleukins; D053773:Transforming Growth Factor beta1; D014409:Tumor Necrosis Factor-alpha