Dyskeratosis congenita 1(DKC1) is also known as dyskerin. DKC1 is required for ribosome biogenesis and telomere maintenance. It is a probable catalytic subunit of H/ACA small nucleolar ribonucleoprotein (H/ACA snoRNP) complex, which catalyzes pseudouridylation of rRNA. DKC1 is also required for correct processing or intranuclear trafficking of TERC, the RNA component of the telomerase reverse transcriptase (TERT) holoenzyme. Defects in DKC1 are a cause of dyskeratosis congenita X-linked recessive (XDKC), a rare progressive bone marrow failure syndrome [taken from the Universal Protein Resource (UniProt) www.uniprot.org/uniprot/O60832].