Thus, there will not be only ‘high’ or ‘low’ MITF activity, but ‘differential’ activity, and assigning MITF only one particular function or phenotype at a certain level, as it is carried out in the rheostat model (Carreira et al., 2006) might be too restrictive, and we have to consider new ways of describing MITF function in melanoma. Here, MITF is linked to melanoma.