TYR and oculocutaneous albinism: However, that report was published in the pregenetics diagnostic era and, in absence of specific information about the genetic type of albinism suffered by these cases, it cannot be excluded that residual tyrosinase activity was actually present in these subjects.52 Indeed, because of the clinical overlap between oculocutaneous albinism (OCA) subtypes, molecular diagnosis is necessary to establish the specific gene defect and thus the OCA subtype.