Northern blot analysis for the expression of clone no. 4 and GAPDH in leukemia cell lines, normal bone marrow, and patient C.D., showing clone no. 4 mRNA in K562 cells (lane 1, P39; lane 2, Molt 4; lane 3, K562; lane 4, HEL; lane 5, CEM; lane 6, normal bone marrow; lane 7, patient C.D.).