Genomic organization of the Atlantic salmon hemoglobin gene clusters. A) Schematic representation of the region of Atlantic salmon chromosome 6 containing the hemoglobin genes. Sequence reads for this region assembled into one solid sequence contig (ctg 41). B) Schematic representation of the region of Atlantic salmon chromosome 3 containing the hemoglobin genes. Sequence contigs are indicated by horizontal green lines. β hemoglobin genes are indicated in blue; α hemoglobin genes are indicated in red. Arrows indicate strand of transcription. All hemoglobin gene names begin with SsaChr6 or SsaChr3 for chromosome 6 and chromosome 3, respectively, followed by α or β and a number indicating the order of the genes. SP6 and T7 ends of overlapping BACs are indicated by grey arrows. Thus, the regions between the arrows indicate BAC overlapping regions. bN: Non-Bohr β hemoglobins.