Genomic analysis of acute myeloid leukemia: potential for new prognostic indicators

Acute myeloid leukemia (AML) is a heterogeneous group of clonal myeloid malignancies. With a few exceptions, response to treatment is unsatisfactory and prognosis is poor. Studies indicate that specific cytogenetic abnormalities, identified by classical G-banding, correlate with prognosis. These findings advanced the ability to predict outcome and to tailor treatments in AML. These studies also suggested that a more detailed analysis of somatic genomic mutations might extend these advances.

New technologies, including DNA arrays and automated sequencing, have improved detection of subtle, acquired genomic alterations. DNA array based screening approaches permit detection of copy number alterations (CNAs) of less than 5 Mb in size. Subchromosomal copy number neutral loss of heterozygosity (CNN-LOH) can also be detected using approaches that take advantage of single nucleotide polymorphisms in the human genome. However, identification of single nucleotide variants in leukemic clones still requires targeted or massive sequencing approaches.

Recent studies suggest that CNAs and CNN-LOH occur frequently in AML. Recurring abnormalities have been identified which may be relevant to disease pathogenesis. However, larger studies will be required to determine the relevance of these alterations to prognostic prediction or therapeutic targeting.