Table 1.

Mutations in epigenetic regulators in MDS and AML.

Gene	Mutation Effect on Gene	Mutational Frequency	Characteristics
ASXL1 [42,43,44,45]	Loss-of-function mutation	20% in MDS	Mutations enriched in elderly AML and sAML patients
		6–30% in AML
BCOR [46,47,48]	Loss-of-function mutation	5% in MDS	Associated with poor prognosis
		9% in AML
DNMT3A [49,50,51,52,53,54]	Loss-of-function mutation	13% in MDS	Thought to be initiating mutation during the pre-leukemic state
		20% in AML	Important for the balance of differentiation and self-renewal
EZH2 [55,56,57,58,59]	Loss-of-function mutation as well as gain of function mutations	5% in MDS	Thought to regulate the balance between self-renewal and differentiation
		1–2% de novo AML	In MDS associated with poor prognosis
IDH1/2 [60,61,62,63,64,65]	Gain of function	5% in MDS	Leads to the production of oncometabolite, which interferes with TET2 activity and histone demethylases
		20% in AML	IDH2 mutations are more common
RUNX1 [66,67,68,69,70,71]	Translocations	10–20% in MDS	Significantly associated with EZH2 mutations
	Loss-of-function mutation	2–20% in AML
Cohesin [72,73,74,75,76,77]	Loss-of-function mutation	10–15% in MDS,	Mutually exclusive
		10% in AML	often associated with mutations in NPM1, TET2, ASXL1 and EZH2
TET2 [78,79,80,81,82,83,84,85]	Loss-of-function mutation	30–50% in MDS	Important for myeloid differentiation and lineage commitment
		30% in sAML	Associated with poor prognosis in some studies