DKC1 and cancer: As far as the first hypothesis is concerned, a systematic analysis of the DKC1 gene sequence in mutational hotspots, in human sporadic cancers of different types, showed that DKC1 mutations are not a frequent event, and cannot be considered the cause of reduced dyskerin expression [74], thus suggesting that, in sporadic tumors, dyskerin expression may undergo some kind of (post-)transcriptional regulation.