Table 2.
Common genetic polymorphisms (Single Nucleotide Polymorphisms-SNP) associated with thyroid hormone axis and response to therapy.
| References | Polymorphism(s) | Gene | Function | Finding | Notes |
|---|---|---|---|---|---|
| Mentuccia et al. (29) Panicker et al. (32) | Thr92Ala rs225014 | Type 2 deiodinase (DIO2) | T4 → T3 conversion | Decreased activity, associated with improved response to LT3:LT4 therapy | Synergistic effects with other polymorphisms |
| Peeters et al. (30) | Asp727Glu rs1991517 | TSH receptor (TSH-R) | TSH receptor | Lower TSH levels, no changes in thyroid hormone | |
| Peeters et al. (30) | C785T rs11206244 | Type 1 deiodinase (DIO 1) | rT3 → T2 T4 → T3 conversion | Correlation between the T allele and rT3 levels | Interpreted as loss of function |
| Peeters et al. (30) | A1814G rs12095080 | Type 1 deiodinase (DIO1) | rT3 → T2 T4 → T3conversion | Correlation between the G allele and rT3 levels | Interpreted as gain of function |
| Peeters et al. (31) | D2-ORFa-Gly3Asp −258 A/G rs12885300 | Type 2 deiodinase (DIO2) | T4 → T3 conversion | Increased activity, changes in serum T3:FT4 ratio | |
| Medici et al. (33) | rs1382879 rs2046045 rs9687206 rs12515498 rs832790 rs1351283 rs989758 | Phosphodiesterase 8B (PDE8B) | TSH signal transduction | Association with higher TSH levels | Medici et al. (33) |
| Medici et al. (33) | rs7714529 | Phosphodiesterase 8B (PDE8B) | TSH signal transduction | Association with lower TSH levels | |
| Roef et al. (34) | rs5937843 | Monocarboxylate transporter 8 (MCT8) | T3 cell membrane transporter | inverse association with FT4 concentrations | |
| Roef et al. (34) | rs6647476 | Monocarboxylate transporter 8 (MCT8) | T3 cell membrane transporter | Inverse association with FT3 levels | |
| Carlé et al. (35) | rs17606253 | Monocarboxylate transporter 10 (MCT10) | T3 cell membrane transporter | Carriers of both rs17606253 and rs225014 tend to prefer LT3:LT4 therapy | Synergistic effects with Thr92Ala variant |