Somatic mutations of epigenetic gene regulators are common in patients with 
myelodysplastic syndromes (MDS) and correlate with some clinical and laboratory 
features. We studied mutations in TET2, ASXL1 and EZH2 in 153 Chinese patients 
with MDS. TET2 mutations were detected in 35 patients (23%), ASXL1 in 33 
patients (22%) and EZH2 in 8 (5%). ASXL1 mutations were associated with 
increased colony formation of BFU-E, CFU-E and CFU-GM (P-values, 0.049, 0.011 
and 0.006). EZH2 mutations were common in patients with poor IPSS cytogenetics 
(P=0.001) and in patients in the IPSS intermediate-2/high-risk cohorts (P=0.06). 
In uni- but not multi-variate analyses, mutated TET2 was associated with longer 
survival (P=0.044) whereas EZH2 mutations were associated with an increased risk 
of transformation to acute myeloid leukemia (AML; P=0.039). These data suggest 
ASXL1 mutations might results in dominance of the mutant clone in Chinese with 
MDS whereas EZH2 mutations might predict an increased risk of transformation to 
AML.