Table 1.
Genetic polymorphisms of immune response-related genes associated with ARF and RHD
| Gene | Polymorphism | Effect of polymorphism | Population | Refs |
|---|---|---|---|---|
| MBL2 | −221 X,Y (promoter, exon 1) A (52C, 54G, 57G), O (52T, 54A, 57A) |
High production of mannose-binding protein | Brazilian | 55 |
| A (52C, 54G, 57G), O (52T, 54A, 57A) |
Low level of MBL2 in sera | Brazilian | 56 | |
| FCN2 | −986G>A, −602G>A, −G>A (promoter) | Low levels of FCN2 | Brazilian | 57 |
| TLR2 | 2258A>G (exon 3), resulting in 753 Arg>Gln | Low level of pathogen recognition | Turkish | 58 |
| FCGR2A | 494A>G (exon 4), resulting in 131 His>Arg | Low ability of receptor to bind human IgG2 | Turkish | 59 |
| IL1RN | Variable number of tandem repeats A1, A2 A3, A4 (intron 2) | Low level of receptor expression | Egyptian and Brazilian | 60,61 |
| TNF | −308G>A (promoter) | TH1 and TH2 imbalance | Mexican, Egyptian and Brazilian | 60,62,63 |
| −238G>A (promoter) | High production of TNF | Turkish, Mexican and Brazilian | 63,64 | |
| TGFB1 | −509C>T (promoter) | TH1 and TH2 imbalance | Egyptian | 65 |
| −509C>T (promoter) | Protection from developing RHD | Chinese | 66 | |
| 869T>C (exon 1), resulting in 10 Leu>Pro | Association with elevated serum TGFβ1 | Egyptian | 65 | |
| IL10 | −1082G>A (promoter) | TH1 and TH2 imbalance | Egyptian | 60 |
| CTLA4 | 49A>G (exon 1) | Transmits an inhibitory signal to T cells | Turkish | 67 |
| HLA class II | Diverse HLA-DR alleles located at short arm of chromosome six at DRB1 gene, including DR1, DR2, DR3, DR4, DR5, DR6, DR7 and DR9 | Antigen recognition and antigen presentation to T cells; activation of humoral and cellular immune responses | Several ethnic populations | 68–81 |
AFR, acute rheumatic fever; CTLA4, cytotoxic T lymphocyte-associated protein 4; FCGR2A, Fc fragment of IgG low-affinity IIa receptor; FCN2, ficolin 2; HLA, human leukocyte antigen; IL10, interleukin-10; IL1RN, interleukin-1 receptor antagonist; MBL2, mannose-binding lectin protein C 2; RHD, rheumatic heart disease; TGFB1, transforming growth factor β1; TH, T helper; TLR2, Toll-like receptor 2; TNF, tumor necrosis factor.