Background: Brain-derived neurotrophic factor (BDNF) is involved in the pathophysiology of coronary artery disease (CAD). The human BDNF Val66Met polymorphism has been shown to be associated with altered susceptibility to neuropsychiatric disorders. However it is unknown whether this polymorphism plays a role in cardiovascular disease.

Methods: Genotyping of BDNF Val66Met polymorphism was carried out in 513 controls, 628 unstable angina pectoris (UAP) and 276 stable angina pectoris (SAP) patients. The plasma concentrations of BDNF and highsensitivity C-reactive protein (hsCRP) were measured by ELISA. The general clinical data in patients and controls were obtained.

Results: There was a significant association between genotype and allele frequency of the BDNF Val66Met polymorphism and UAP (all Pb0.05). Multivariate logistic regression analysis revealed that the BDNFMet/Met genotype had a protective effect on the occurrence of UAP after controlling for known risk factors of CAD (OR 0.53, P=0.005). Subjects with BDNFMet/Met genotype also had decreased plasma hsCRP levels compared with the Val carriers (Pb0.01).

Conclusion: The BDNFMet/Met genotype has a protective effect on the occurrence of UAP, which might in part be due to the decreased plasma hsCRP level in BDNFMet/Met carriers. To our knowledge, this is the first study that demonstrates the link between BDNF Val66Met polymorphism and CAD.