CSNK1A1 and myelodysplastic syndrome: However, in a recent study (Schneider et al, 2014), mutations of CSNK1A1 were identified using whole‐exome sequencing in 2 of 19 del(5q) cases and a further CSNK1A1 mutation was found in an additional cohort of 22 MDS cases with isolated del(5q) using next‐generation targeted sequencing, giving an overall frequency of approximately 7% in the MDS del(5q) cases analysed.