The COMT val158met polymorphism is associated with peak BMD in men

Area of Science:

• Genetics
• Bone Biology
• Endocrinology

Background:

• Peak bone mineral density (BMD) is a key factor in predicting osteoporosis risk, with genetics playing a significant role.
• Estrogens are crucial for bone mass accrual during puberty, and the catechol-O-methyltransferase (COMT) enzyme regulates estrogen degradation.
• A common functional polymorphism in the COMT gene (val158met) affects enzyme activity, influencing estrogen metabolism.

Purpose of the Study:

• To investigate the association between the COMT val158met polymorphism and skeletal properties, specifically peak bone mineral density (BMD), in young men.

Main Methods:

• 458 healthy young men were genotyped for the COMT val158met polymorphism (LL, HL, HH).
• Bone mineral density was assessed using dual-energy X-ray absorptiometry (DXA) for areal BMD (aBMD) and peripheral quantitative computed tomography (pQCT) for volumetric BMD (vBMD).
• Statistical models analyzed the relationship between COMT genotype and skeletal phenotypes.

Main Results:

• COMT genotype was an independent predictor of total body and femur aBMD, but not spinal aBMD.
• Individuals with the COMT LL genotype (low enzyme activity) exhibited significantly lower aBMD compared to the HL/HH groups (higher activity) at the total body and femur.
• COMT genotype also predicted trabecular vBMD in the tibia, radius, and fibula, with the LL genotype showing lower values.

Conclusions:

• The COMT val158met polymorphism is significantly associated with bone mineral density in young adult men.
• The low-activity COMT genotype (LL) is linked to reduced bone density at various skeletal sites.
• These findings highlight the role of estrogen metabolism, influenced by COMT genotype, in determining bone mass in young men.