Interleukin-6 (IL-6) -572C-->G promoter polymorphism is associated with type 2 diabetes risk in Koreans.
OBJECTIVE
Increased levels of inflammatory markers, such as interleukin-6 (IL-6), are associated with type 2 diabetes (T2DM). We investigated the association of IL-6 gene polymorphisms with T2DM and circulating levels of IL-6 in Koreans.


METHODS
A total of 1477 subjects with normal glucose tolerance and 476 T2DM patients were included.


METHODS
We examined IL-6 -174G-->C, -572C-->G, -597G-->A and -1363G-->T promoter region polymorphisms. The main outcome measures were the odds ratio (OR) on T2DM risk and serum concentrations of IL-6 and high-sensitivity C-reactive protein (hs-CRP).


RESULTS
Homozygosity for the rare G allele IL-6 -572C-->G was associated with a higher risk of T2DM [OR 1.69 (95%CI 1.11-2.58), P = 0.015]. Serum IL-6 concentrations were associated with the IL-6 -572C-->G genotype in control subjects (G/G: 2.33 +/- 0.41: C/G: 1.53 +/- 0.09: C/C: 1.72 +/- 0.08 ng/l, P = 0.023). Also in the control group, subjects homozygous for the rare G allele showed significantly higher concentrations of hs-CRP than C/C and C/G carriers (G/G: 13.6 +/- 2.9: C/G: 9.2 +/- 0.6: C/C: 7.8 +/- 0.4 mg/l, P = 0.003). The C-allele at the IL-6 -174 SNP was very rare (< 0.01) and -597G-->A and -1363G-->T were monomorphic in this population.


CONCLUSIONS
Our data demonstrate that the IL-6 -572G/G genotype is associated with higher serum IL-6 and hs-CRP concentrations and with increased risk for T2DM.
Yonsei University Research Institute of Science for Ageing, Yonsei University, Seodaemun-Gu, Seoul, Korea.
Soo Jeong
SJ
Koh
Yangsoo
Y
Jang
Yae Jung
YJ
Hyun
Ju Yeon
JY
Park
Young Duk
YD
Song
Kyung-Kyun
KK
Shin
Jey Sook
JS
Chae
Byung-Keuk
BK
Kim
Jose M
JM
Ordovas
Jong Ho
JH
Lee
D000328:Adult; D000368:Aged; D001786:Blood Glucose / Q000378:metabolism; D002097:C-Reactive Protein / Q000378:metabolism; D016022:Case-Control Studies; D003924:Diabetes Mellitus, Type 2 / Q000453:epidemiology* / Q000208:ethnology* / Q000235:genetics; D005260:Female; D005838:Genotype; D006720:Homozygote; D006801:Humans; D007328:Insulin / Q000097:blood; D015850:Interleukin-6 / Q000097:blood / Q000235:genetics*; D007723:Korea; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D011401:Promoter Regions, Genetic / Q000235:genetics*; D012307:Risk Factors
D001786:Blood Glucose; D007328:Insulin; D015850:Interleukin-6; D002097:C-Reactive Protein