OCA2 and oculocutaneous albinism: OCA is subdivided into 7 subtypes (OCA 1–7) based on genes as follows: TYR (OCA1), OCA2 (OCA2), TYRP1 (OCA3), SLC45A2(OCA4), SLC24A5 (OCA6), LRMDA (OCA7) and OCA5 located on chromosome 4q24 and the subtypes can only be accurately diagnosed by genetic gene [3].