RATIONALE: Studying samples of blood or tumor tissue from patients with cancer in the laboratory may help doctors learn about changes that occur in DNA and identify biomarkers related to cancer.

PURPOSE: This research study is studying biomarker changes in samples from young patients with acute myeloid leukemia.

OBJECTIVES:

• Map key histone modifications and cytosine methylation in leukemia cell lines with defined oncogenic mutations.
• Acquire genome-wide maps of key histone modifications and cytosine methylation for primary leukemia in samples from patients with acute myeloid leukemia (AML).
• Investigate functional relationships between genetic and epigenetic landscapes in AML.

OUTLINE: Archived samples are analyzed in vivo and in vitro (cell line) for histone modification and cytosine methylation. Genome-wide locations of 5 histone modifications are analyzed using chip-Seq, as well as DNA methylation analysis at nucleotide-resolution by high-throughput bisulfite sequencing. These epigenetic data are correlated with genomic data (sequence analysis, expression array, SNP array).

DISEASE CHARACTERISTICS:

• Diagnosis of acute myeloid leukemia
• Primary leukemia samples from the Children Oncology Group (COG) bank with sufficient number of cells (500,000-1 million cells) with > 80% of leukemia blasts

PATIENT CHARACTERISTICS:

• Not specified

PRIOR CONCURRENT THERAPY:

• Not specified

Diagnosis of acute myeloid leukemia