CLONING AND CHARACTERIZATION OF THE T(XII) BREAKPOINT FROM A LEUKEMIC-CELL LINE IDENTIFY A NEW MEMBER OF THE FORKHEAD GENE FAMILY

Chromosome translocations involving 11q23 are associated with a number of different types of leukemia. These translocations fuse a gene enco ding a putative transcription factor, HTRXI, to genes on other chromos omes. We report cloning and sequencing the t(X;11) breakpoint region f rom a cell line established from an infant with acute lymphocytic leuk emia. The gene AFXI, on the X chromosome, is expressed in a variety of cell types. Sequence analysis indicates a high degree of homology bet ween AFXI and the forkhead family of transcription factors. The high d egree of identity within the forkhead region and the lack of homology outside that region suggest that AFXI represents a novel forkhead fami ly member. It is predicted that a chimeric fusion protein with altered DNA binding activity will be the result of the translocation. Genes C hromosom Cancer 11:79-84 (1994). (C) 1994 Wiley-Liss, Inc.