Association of Interleukin-1 gene polymorphisms with central obesity and metabolic syndrome in a coronary heart disease population.

Abstract

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.

• Authors: Kim W Carter, Joseph Hung, Brenda L Powell, Steven Wiltshire, Brendan T X Foo, Yuen C Leow, Brendan M McQuillan, Michelle Jennens, Pamela A McCaskie, Peter L Thompson, John P Beilby, Lyle J Palmer
• Journal: Human genetics (Hum Genet) Vol. 124 Issue 3 Pg. 199-206 (Oct 2008) ISSN: 1432-1203 [Electronic] Germany
• PMID: 18716798 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Interleukin-1
• Fibrinogen

Topics

• Adult
• Alleles
• Body Mass Index
• Coronary Disease (complications, genetics)
• Female
• Fibrinogen (biosynthesis)
• Genotype
• Humans
• Inflammation
• Interleukin-1 (genetics)
• Male
• Metabolic Syndrome (complications, genetics)
• Middle Aged
• Obesity (complications, genetics)
• Polymorphism, Single Nucleotide