Ideogram of the genomic organization of the

BCL11A gene, the structure of the t(2;14)(p13;q32.3) translocation, and the predicted primary amino acid sequence ofBCL11A. (A) Ideogram of t(2;14)(p13;q32.3). All 4IGH breaks occurred within Sγ regions, whereas the 2p13 breaks clustered centromeric of a CpG island. Sequence comparison of genomic and expressed sequences from chromosome 2p13 showed the presence of 5 exons with the alternative splices indicated. Shaded arrows denote sites of breakpoints in cloned cases. Comparison of the derived cDNA sequences with the genomic sequence NT_005399.3 showed the presence of 3 common exons to all common BCL11A RNA isoforms: exon 1 represented nucleotides 370479-370761; exon 2, 377671-378005; and exon 3, 455146-455254. The longest isoform comprised exons 1-4 (exon 4, nucleotides 461558-466783), whereas the 2 common shorter isoforms exhibited alternative splicing from within exon 4 to an additional exon (exon 5, 471315-472815). (B) Predicted amino acid sequence of the longest detected BCL11A RNA isoform showing the presence of 6 C₂H₂ motifs (shown in blue), a sequence of 21 consecutive acidic amino acids shown in red, and a proline-rich region between the first and second zinc fingers, shown in green (accession no. AJ404611).