Molecular Heterogeneity in Childhood Precursor B Acute Lymphoblastic Leukemia with Immunoglobulin Heavy Chain Gene in Germline Configuration

Abstract

Four childhood acute leukemias with morphological, cytochemical and immunological characteristics correlating to precursor B lymphocyte and with germline configuration of the immunoglobulin heavy chain joining region were studied for the organization of the Cμ segment. Two of the four lymphoblast samples retained the germline configuration of both JH and Cμ regions. The other two samples showed delection of the entire JH region resulting in the rearrangement of the Cμ region. In contrast to patients with Cμ rearrangement, patients with Cμ in germline form were not able to achieve complete remission after induction therapy. Study of the Cμ region in patients with JH segment in germline configuration could separate subgroups in childhood precursor B acute lymphoblastic leukemia with different prognoses.

Key Words:

• acute lymphoblastic leukemia
• immunoglobulin heavy chain gene
• joining regions
• constant region