UQCC2 and Abnormality of skin pigmentation: Assessing the age and phenotype of the MNF1 diagnosis, our data show that the median age at diagnosis of patients with pigmentary changes only (n = 8) was nine years, whereas the median age at diagnosis of patients with plexiform neurofibromas (n = 2) and neurofibromas only (n = 5) was 28 years and 40 years, respectively.