USB1 and dyskeratosis congenita: Most DKC patients have short telomere lengths (Vulliamy et al., 2001) and are associated with 14 genes: ACD, DKC1, TERC, TERT, NOP10, NHP2, TINF2, USB1, TCAB1, CTC1, PARN, RTEL1, WRAP53, and C16orf57 (Islam et al., 2013; Kilic & Cekic, 2016; Pagon et al., 1993).