Mutations of AML1 in non-MO acute myeloid leukemia: Six novel mutations and a high incidence of cooperative events in a South-east Asian population

Point mutations of AML1 are uncommon and predominantly reported in a rare minimally differentiated acute myeloid leukemia (MO AML). Few data exist regarding the frequency of AML1 mutations in non-MO cases. We screened 284 consecutive adult Thai patients with de novo AML and found that 3.9% had AML1 mutations. The highest incidence occurred in M6. Six novel mutations were uniquely identified in non-MO cases. Sixty-four percent of the non-MO patients with AML1 mutations had coexisting genetic abnormalities including FLT3 mutation in 36%. Our study provides evidence to support the model of multiple co-operating events, which could also be critical in the development of leukemia in non-MO AML patients with mutated AML1. The prognostic significance of these novel mutations remains to be determined.