To study the genomics with cell cycle and lymphocyte differentiation in disease, remission and relapse of childhood acute lymphoblastic leukemia. Then correlate these data with age, white cell count, cytogenetic changes, response to the chemotherapy and prognosis.

In order to know the genomic evolution of childhood acute lymphoblastic leukemia, we will collect bone marrow (10c.c.) at diagnosis, remission and relapse. We will do the following genes in addition to gene-chip including IKZF1,ETV6, EBF1, NR3C1, RAG1/G2, TCF3, BTLA, PAX5,LEF1, ERG and VPREB1.We will study the gene dosages and degree of methylation. The estimated patients numbers will be 300-400. Then we will correlate these data with patients'age, white blood cell count at diagnosis, cytogenetic abnormalities, response to the chemotherapy and prognosis.

Inclusion Criteria:

1. patients diagnosed as acute lymphoblastic leukemia
2. age less than or equal to 18 years old
3. signed informed consent

Exclusion Criteria:

1. who is not acute lymphoblastic leukemia
2. who did not sign informed consent

Acute lymphoblastic leukemia patients under 18 years of age