Rearrangement of the myeloid-lymphoid leukaemia gene in Hong Kong Chinese children with acute leukaemia.

OBJECTIVE To determine the frequency of rearrangement of the myeloid-lymphoid leukaemia gene in acute leukaemia in Hong Kong Chinese children. DESIGN Immunophenotyping, cytogenetic, and molecular analysis. SETTING Regional hospital, Hong Kong. PARTICIPANTS Bone marrow or peripheral blood samples were taken from 27 children aged 16 years or younger with acute leukaemia, from September 1995 through February 1998. MAIN OUTCOME MEASURES Gene rearrangement was analysed by Southern blotting of HindIII digestion products of mononuclear cell DNA, followed by hybridisation with the myeloid-lymphoid leukaemia P/S4 probe. Nested reverse transcription-polymerase chain reaction analysis was performed to detect and characterise duplication of the myeloid-lymphoid leukaemia gene. RESULTS Only one (4%) of 23 children whose marrow or peripheral blood samples contained adequate material for genetic study showed rearrangement in the myeloid-lymphoid leukaemia gene. No children were positive for partial tandem duplication of the myeloid-lymphoid leukaemia gene. CONCLUSION Myeloid-lymphoid leukaemia gene rearrangement is rare in Hong Kong Chinese children with acute leukaemia.