Interleukin-1beta and interleukin-1 receptor antagonist gene polymorphism in postmenopausal women: correlation to bone mineral density and susceptibility to osteoporosis.
OBJECTIVE
Osteoporosis is a common disorder with a strong genetic component. Our aim was to investigate the correlations of the interleukin-1beta (IL-1beta) and interleukin-1 receptor antagonist (IL-1Ra) gene polymorphisms with bone mineral density (BMD) and their relationship to osteoporosis.


METHODS
The IL-1beta (promoter and exon 5) and IL-1Ra (intron 2) gene polymorphisms were determined using polymerase chain reaction. BMD of the lumbar spine and proximal femur were measured using dual-energy X-ray absorptiometry.


RESULTS
The prevalence of each genotype of the interleukin-1 related genes in the study population was: (1) 14% C/C, 71.5% C/T, and 14.5% T/T in IL-1beta promoter; (2) 95.3% E1/E1 and 4.7% E1/E2 in IL-1beta exon 5; (3) 92.4% I/I, 6.4% I/II, and 1.2% II/II in IL-1Ra intron 2. After adjustment for potential confounding factors such as age, height, weight, years since menopause, and daily calcium intake, subjects with genotype E1/E2 (n=8) in IL-1beta exon 5 had lower BMD values and a significantly greater risk for osteoporosis (OR 10.6, 95% CI 1.3-83.8) at the lumbar spine when compared with subjects with genotype E1/E1 (n=164) in IL-1beta exon 5.


CONCLUSIONS
The Taq I IL-1beta exon 5 gene polymorphism is associated with reduced BMD and predisposes women to osteoporosis at the lumbar spine, but our results should be interpreted with caution because of the small number of subjects with the unfavorable E1/E2 genotype.
Chen
Huey-Yi
HY
Department of Obstetrics and Gynecology, China Medical College Hospital, School of Medicine, China Medical College, Taichung, Taiwan.
Chen
Wen-Chi
WC
Wu
Mei-Chen
MC
Tsai
Fuu-Jen
FJ
Lin
Cheng-Chieh
CC
D015519:Bone Density; D005260:Female; D005272:Femur Neck; D006801:Humans; D053590:Interleukin 1 Receptor Antagonist Protein; D007375:Interleukin-1 / Q000235:genetics*; D008159:Lumbar Vertebrae; D008875:Middle Aged; D015663:Osteoporosis, Postmenopausal / Q000235:genetics*; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D017698:Postmenopause; D012795:Sialoglycoproteins / Q000235:genetics*
C507763:IL1RN protein, human; D053590:Interleukin 1 Receptor Antagonist Protein; D007375:Interleukin-1; D012795:Sialoglycoproteins