RATIONALE: Studying bone marrow samples from patients with cancer in the laboratory may help doctors learn more about changes that occur in DNA and identify biomarkers related to cancer.

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

OBJECTIVES:

• To compare the frequency of germline telomerase mutations in pediatric patients with acute myeloid leukemia (AML) demonstrating prolonged myelosuppression, defined as ≥ 1 episode > 35 days of neutrophil count recovery after chemotherapy, to the pediatric patients with the expected myelosuppression, defined as consistently < 35 days of neutrophil count recovery after chemotherapy.
• To assess association between telomerase mutations and incidence of grade 3 or 4 mucositis, relapse, and death.
• To compare germline (remission) telomere length in pediatric AML patients demonstrating delayed bone marrow recovery with the pediatric patients with consistently expected recovery.
• To assess whether a correlation between telomere length and incidence of grade 3 or 4 mucositis, relapse, and death exist.

OUTLINE: This is a multicenter study.

Cryopreserved bone marrow samples are analyzed for DNA sequencing and mutation by Sanger-based sequencing methods, quantitative PCR, and SeqMan Pro (Lasergene from DNAStar). Results are then compared with previously published data and existing databases to determine the allele frequency in control populations.

DISEASE CHARACTERISTICS:

• Diagnosis of acute myeloid leukemia

• Enrolled on CCG-2961 and meeting 1 of the following criteria:

  • More than 35 days to recover to an ANC > 500/mm³ after any course of chemotherapy
  • Consistently recovered < 35 days to an ANC > 500/mm³ after all courses of chemotherapy

• Available cryopreserved cell from diagnostic and end-of-therapy samples

PATIENT CHARACTERISTICS:

• Not specified

PRIOR CONCURRENT THERAPY:

• See Disease Characteristics

Diagnosis of acute myeloid leukemia.