Associations of catalase gene polymorphisms with bone mineral density and bone turnover markers in postmenopausal women.
BACKGROUND
Oxidative stress has been recently suggested to play a part in the development of osteoporosis. Catalase is a major antioxidant enzyme that detoxifies hydrogen peroxide by converting it into water and oxygen, thereby preventing cellular injury by oxidative stress.


OBJECTIVE
To examine the associations between the catalase gene (CAT) polymorphisms and bone mineral density (BMD) and bone turnover markers in postmenopausal Korean women.


METHODS
All exons, their boundaries and the promoter region (approximately 1.5 kb) were directly sequenced in 24 individuals. Among 18 variants identified by a direct sequence method, four polymorphisms were selected and genotyped in all study participants (n = 560). BMD at the lumbar spine and proximal femur was measured using dual-energy x ray absorptiometry. Serum osteocalcin concentrations and bone-specific alkaline phosphatase activity were determined by an immunoradiometric assay and an immunoassay, respectively.


RESULTS
The mean (standard deviation) age of the participants was 59.4 (7.2) years. Multivariate analysis showed an association of the +22348C-->T polymorphism with BMD at the lumbar spine (p = 0.01 in the dominant model) and at femur neck (p = 0.05 in the dominant model), and with serum osteocalcin level (p = 0.008 in the dominant model). Haplotype analyses showed that HT4 (-20T, +144C, +22348T, +33078A) was significantly associated with higher BMD at various sites (p<0.001-0.03) and with lower serum osteocalcin levels (p = 0.01 in the codominant model).


CONCLUSIONS
These findings indicate that the +22348C-->T polymorphism and HT4 of CAT may be useful genetic markers for bone metabolism.
Oh
Bermseok
B
Kim
Shin-Yoon
SY
Kim
Duk Jae
DJ
Lee
Jong Yong
JY
Lee
Jong-Keuk
JK
Kimm
Kuchan
K
Park
Byung Lae
BL
Shin
Hyoung Doo
HD
Kim
Tae-Ho
TH
Park
Eui Kyun
EK
Koh
Jung-Min
JM
Kim
Ghi Su
GS
D000368:Aged; D000469:Alkaline Phosphatase / Q000097:blood; D044466:Asian People / Q000235:genetics; D015519:Bone Density / Q000235:genetics*; D002374:Catalase / Q000235:genetics*; D005260:Female; D005819:Genetic Markers; D006239:Haplotypes; D006801:Humans; D008875:Middle Aged; D015675:Osteocalcin / Q000097:blood; D015663:Osteoporosis, Postmenopausal / Q000235:genetics* / Q000378:metabolism; D018384:Oxidative Stress; D020641:Polymorphism, Single Nucleotide; D013131:Spine / Q000473:pathology
D005819:Genetic Markers; D015675:Osteocalcin; D002374:Catalase; D000469:Alkaline Phosphatase