DKC1 and dyskeratosis congenita: Considering that many of the disease-causing mutations found in Dkc1 have been shown to disrupt the binding and/or stability of a select subset of mammalian snoRNAs which we have shown could play a critical role in conferring coactivator competence to the DKC1 complex, it was somewhat surprising that neither the enzymatic activity nor amino acids mutated in dyskeratosis congenita (DC) patients negatively impacted coactivator activity.