Association of Interleukin-1 gene polymorphisms with central obesity and metabolic syndrome in a coronary heart disease population.
The objective of this study was to determine whether single nucleotide polymorphisms (SNPs) in the Interleukin-1 (IL-1) gene family are associated with central obesity and metabolic syndrome in a coronary heart disease population. The IL-1 alpha C-889T (rs1800587) and IL-1 beta +3954 (rs1143634) SNPs were studied in a Western Australian coronary heart disease (CHD) population (N = 556). Subjects who were TT homozygous at either SNP had larger waist circumference (IL-1 alpha: 1.8 cm greater, P = 0.04; IL-1 beta: 4 cm greater, P = 0.0004) compared with major allele homozygotes. Individuals with two copies of the IL-1 alpha:IL-1 beta T:T haplotype had greater waist circumference (4.7 cm greater, P = 0.0001) compared to other haplotypes. There was a significant interaction between the IL-1 beta SNP and BMI level on waist circumference (P = 0.01). When the cohort was stratified by median BMI, TT carriers for IL-1 beta with above median BMI had greater waist circumference (6.1 cm greater, P = 0.007) compared to baseline carriers, whilst no significant association was seen in the below median group. Similarly, when the cohort was stratified by median fibrinogen level (IL-1 alpha interaction P = 0.01; IL-1 beta interaction P = 0.04), TT carriers for both SNPs in the above median fibrinogen group had greater waist circumference (IL-1 alpha 2.7 cm greater, P = 0.007; IL-1 beta 3.3 cm greater, P = 0.003) compared with major allele homozygotes. This association was not seen in the below median group. Also, we found a trend of increased metabolic syndrome for IL-1 beta TT homozygotes (P = 0.07). In conclusion, our findings suggest that in a CHD population IL-1 gene polymorphisms may be involved in increased central obesity, and the genetic influences are more evident among patients who have a higher level of obesity or inflammatory markers.
Carter
Kim W
KW
Western Australian Institute for Medical Research and UWA Centre for Medical Research, University of Western Australia, Perth, WA, Australia. kcarter@ichr.uwa.edu.au
Hung
Joseph
J
Powell
Brenda L
BL
Wiltshire
Steven
S
Foo
Brendan T X
BT
Leow
Yuen C
YC
McQuillan
Brendan M
BM
Jennens
Michelle
M
McCaskie
Pamela A
PA
Thompson
Peter L
PL
Beilby
John P
JP
Palmer
Lyle J
LJ
D000328:Adult; D000483:Alleles; D015992:Body Mass Index; D003327:Coronary Disease / Q000150:complications* / Q000235:genetics; D005260:Female; D005340:Fibrinogen / Q000096:biosynthesis; D005838:Genotype; D006801:Humans; D007249:Inflammation; D007375:Interleukin-1 / Q000235:genetics*; D008297:Male; D024821:Metabolic Syndrome / Q000150:complications* / Q000235:genetics*; D008875:Middle Aged; D009765:Obesity / Q000150:complications* / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide
D007375:Interleukin-1; D005340:Fibrinogen