TABLE 1.
A selection of some of the most relevant gene polymorphisms linked to hair, skin and eye pigmentation phenotype
| Pigmentation related gene | Expression product | Function | Selected variants | Relevant to the vitamin D‐folate hypothesis |
|---|---|---|---|---|
| TYR | Tyrosinase enzyme | Melanogenesis | rs1042602 | ? |
| GMR5 | Glutamate metabotropic receptor 5 | Tyrosine expression | rs10831496 | ? |
| IRF4 | Interferon regulatory factor 4 | Tyrosine expression | rs12203592 | YES |
| HERC2 | HECT and RLD domain containing E3 ubiquitin ligase 2 | Regulation of OCA2 expression and hence melanogenesis |
rs12913832 rs4932620 rs649721 |
YES |
| OCA2 | Oculocutaneous albinism 2 (melanocyte‐specific transporter protein/pink‐eyed dilution protein homolog) | Melanogenesis |
rs1800404 rs1800414 rs74653330 rs7495174 |
? |
| APBA2 | Amyloid beta A4 precursor protein‐binding family A member 2 | Potential regulation of OCA2 expression and hence melanogenesis | rs442881 | ? |
| SLC45A2 | Solute carrier family 45 member 2 (membrane associated transporter) | Melanogenesis | rs16891982 | ? |
| SLC24A4 | Membrane transporter (NCKX4) | Na+/Ca2+, K+ exchanger. Eye color | rs12896399 | ? |
| SLC24A5 | Solute carrier family 24 member 5 (NCKX5) | K+ dependent Na+/Ca2+ exchanger (melanogenesis) | rs1426654 | ? |
| MC1R | Melanocortin 1 receptor (G protein‐coupled receptor) | Eumelanin synthesis |
rs1805007 rs42687448 |
? |
| KITLG | KIT Ligand | Melanocyte migration |
rs642742 rs12821256 |
? |
| MFSD12 | Major facilitator superfamily domain containing 12 | Transporter mediating import of cysteine into melanosome, regulating pheomelanin synthesis |
rs10424065 rs2240751 rs2240751 |
? |
| DDB1/TMEM138 | Damage specific DNA binding protein 1/Transmembrane protein 138 | UVR exposure response and DNA damage repair |
rs2513329 rs7948623 rs11230664 |
? |
| TYRP1 | Tyrosinase‐related protein 1 | Melanogenesis | rs115075138 | ? |
| ASIP | Agouti‐signaling protein | Interacts with MC1R to determine whether melanocyte synthesizes pheomelanin or eumelanin |
rs6058017 rs6059655 rs4911414 |
? |
| BNC2 | Zinc finger protein basonuclin‐2 | Potential regulated expression of pigmentation genes | rs10756819 | ? |
| MITF | Melanocyte inducing transcription factor | Controls development and function of melanocytes | rs149617956 | ? |