Sequence analysis of a 1.2 Mb ampliconic region of BTAY. This region was assembled from nine Y-BACs (see Additional file 4). A. Triangular dot-plot analysis of the 1.2 Mb BTAY sequence. Each dot represents a perfect match in a word size of 10 nucleotides . The plot indicates that the BTAY ampliconic region is enriched with internally repetitive units. B. Two direct repeats (DR1 and DR2) and two inverted repeats (IR1 and IR2) were detected in the region. The regions with high arm-to-arm similarity are highlighted in red and blue for DR and IR, respectively. The corresponding repeat regions are also highlighted in the dot-plot. The dark red regions highlight the DRs with similarity over 99.5%; the dark blue regions highlight the IRs with similarity over 99.5%. The light red regions are extended direct repeats with similarity over 99% and the light blue regions are extended inverted repeats with similarity over 98.5%. C. The predicted transcribed regions of ZNF280BY, ZNF280AY, HSFY and TSPY are depicted in different tracks with different colors as indicated in the up-right corner. Scale: bar = 100 kb.