Mannose-binding lectin 2 (Mbl2) gene polymorphisms are related to protein plasma levels, but not to heart disease and infection by Chlamydia

Abstract The presence of the single nucleotide polymorphisms in exon 1 of the mannose-binding lectin 2 (MBL2) gene was evaluated ina sample of 159 patients undergoing coronary artery bypass surgery (71 patients undergoing valve replacement surgery and300 control subjects) to investigate a possible association between polymorphisms and heart disease with Chlamydia infection.The identification of the alleles B and D was performed using real time polymerase chain reaction (PCR) and of the allele C wasaccomplished through PCR assays followed by digestion with the restriction enzyme. The comparative analysis of allelic andgenotypic frequencies between the three groups did not reveal any significant difference, even when related to previousChlamydia infection. Variations in the MBL plasma levels were influenced by the presence of polymorphisms, being significantlyhigher in the group of cardiac patients, but without representing a risk for the disease. The results showed that despite MBL2gene polymorphisms being associated with the protein plasma levels, the polymorphisms were not enough to predict thedevelopment of heart disease, regardless of infection with both species of Chlamydia.Key words: Mannose-binding lectin; Polymorphisms; Heart disease; Chlamydia