Mutations in genes for structural proteins of the ribosome or in other genes involved in ribosome biogenesis or function have been found in rare congenital diseases termed ribosomopathies, including Diamond Blackfan anemia (e.g. RPS19 and RPS24), Shwachman-Diamond syndrome (SBDS), X-linked dyskeratosis congenita (DKC1), cartilage hair hypoplasia (RMRP) and Treacher Collins syndrome (TCOF1, POLR1C and POLR1D) [14], [15], [16], [17], [18]. Here, POLR1D is linked to dyskeratosis congenita.