Considering the functional role of MBL in the immune response of the human host, thepresent study aimed to compare the frequency of allelic variants inMBL2 gene exon 1 between groups of patients with different heartdiseases and healthy control subjects, investigating the possible association of SNPs inthe MBL2 gene and changes in MBL plasma levels, in association withChlamydia infection. Here, MBL2 is linked to infection.