Genetics of Iris Color
- Eye color is determined by the presence and degree of melanin pigment in the iris
- The degree of pigmentation is a polygenic trait
Genes responsible for iris pigmentation
OCA2
- 75% of variance is from the OCA2 gene(chromosome 15)
- single base change rs12913832 T/C within intron 86 of the upstream HERC2 locus explains almost all of the OCA gene iris pigmentation variation
| Locus | Chromosome | Protein | SNP | Amino Acid | Genetic Dz | Reference |
|---|---|---|---|---|---|---|
| TYR | 11q14.3 | Tyrosinase | rs1042602 C>A | Ser 192 TYR | Oculocutaneous Albinism type 1 | Frudakis et. al. 2003 Sulem et al. 2007 Liu et al. 2009 |
| rs1800422 G>A | Arg402Gln | |||||
| rs 1126809 G>A | ARG402Gln | |||||
| rs1393350 G>A | ||||||
| TYRP1 | 9p23 | TYRP1 | rs1408799 C<T | Oculocutaneous Albinism type 3 | Frudakis et. al. 2003 Sulem et al. 2007 Liu et al. 2009 | |
| rs2733832 C>T | ||||||
| rs683 C>A | ||||||
| DCT | 13q32 | DCT, TRYP2 | Frudakis et. al. 2003 | |||
| OCA2-HERC2 | 15q11.2-q12 | P-protein | rs1800401 C>T | Arg305Trp | Oculocutaneous Albinism type 2 | Frudakis et. al. 2003 Liu et al. 2009 |
| rs1800407 G>A | Arg419Gln | |||||
| rs1800414 A>G | His615Arg | |||||
| rs12913832 T>C | ||||||
| ASIP | 20q11.22 | ASIP | rs4911442 A>G | Frudakis et. al. 2003 | ||
| rs6058017 A>G | ||||||
| rs6058017(8818 A>G) | ||||||
| rs4911414 G>T | ||||||
| SILV | 12q13-q14 | Silver | Frudakis et. al. 2003 | |||
| MYO5A | 15q21 | MyosinVa | Griscelli syndrome | Frudakis et. al. 2003 | ||
| IRF4 | 6p25.3 | rs12203592 C>T | ||||
| rs1540771 G>A | Han et al. 2008 | |||||
| SLC24A4 | 14q32.12 | SLC24A4 | rs12896399 G>T | Sulem et al. 2007 |