Fluorescence <i>in situ</i> hybridization revealed the localization of tandem repeats in centromeric/pericentromeric regions of the Asian seabass genome and characterization of B chromosomes.

<p>Labeled painting B chromosomes and tandem repeat probes were hybridized to metaphase chromosomes. The chromosomal position of three tandem repeats (green): (A) Sat_LM- centromeres; (B) Lca_217 and Lca_38 (C) pericentromeric region. (D) B chromosome-derived probes, ChB5 (green) and ChB6 (red), reveal the presence of a B chromosome in the <i>L</i>. <i>calcarifer</i> karyotype, as indicated by arrowhead. Chromosomes were counterstained with DAPI (blue). Bar is 10 μm for all images. (E) Association of B chromosomes with the linkage groups. Each linkage group is represented in coloured blocks, and the shadings delineate the genome superscaffolds (after optical mapping) that were assigned to the given linkage group. Rearrangements of portions from the four linkage groups, namely LG5, LG9, LG17 and LG19, together with regions without linkage group assignment (U) comprised the B chromosome.