Abstract: AIM:To investigate the association between the polymorphism in exon 11 of MEF2A and premature coronary artery disease (CAD) in the Yuebei area of Guangdong. METHODS: The variation analysis of exon 11 of MEF2A gene was performed using polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and DNA direct sequencing in 210 sporadic patients with CAD and 180 controls without CAD and its correlation with CAD was analyzed. RESULTS: Frequencies of the classical risk factors for CAD such as hypertension, diabetes and smoking were higher in patients than in controls (P<0.05). CAG repeat polymorphism was detected in exon 11 of MEF2A gene and the number of CAG repeats ranged from 4 to 11, with no significant difference in the distribution of CAG alleles between patients with CAD and controls. No 21-bp deletion was detected in any subject of the study population. Logistic regression analysis revealed that only diabetes was an independent risk factor for CAD (P<0.01). CONCLUSION: CAG repeat polymorphism in exon 11 of MEF2A gene is not a risk factor for premature CAD in Yuebei area.