Figure 1

Dot-plot comparisons between Antarctic minke whale (horizontal, left) or dolphin (horizontal, right) and cow (vertical) sequences. Color scale bar indicates sequence similarity (%) of each dot. a. Comparisons of the genomic region where the OMACS gene is encoded. Cow sequence: chr. 25 (18,535,000-18,568,000 bp). Whale: scaffold100261 (1–18,000 bp, complement). Dolphin: scaffold4608 (95,000-115,000 bp, complement). The OMACS gene consists of 13 exons, and the position and the coding direction of each exon is shown as a triangle with an exon-specific color. Whale and dolphin have lost the genomic regions where the 5^th, 9^th, 10^th and 11^th exons are encoded. In addition, dolphin has lost the 1^st and 2^nd exons. Whale’s 1^st exon is not included in this scaffold (see Additional file 1 for detail). Mesh size, 1 kbp × 1 kbp. b. Comparison of the genomic region where the NQO1 gene is encoded. Cow sequence: chr. 18 (36,908,355-36,927,688 bp). Whale: scaffold73885. Dolphin: scaffold317 (290,000-300,000 bp). The NQO1 gene consists of six exons, and the position and the coding direction of each exon are shown as a triangle with an exon number. Genomic inversion was confirmed in the whale and dolphin genomes around the region where the 4^th and 5^th exons are encoded. Whale’s 1^st exon is not included in this scaffold (see Additional file 1 for detail). Mesh size, 1 kbp × 1 kbp. c. Comparison of the genomic region where the TAAR gene cluster is located. Cow sequence: chr. 9 (71,400,000-71,850,000 bp, complement). Whale: scaffold12993. Dolphin: scaffold181 (230,000-270,000 bp, complement). Positions and coding directions of TAAR1-9 genes are shown. Pseudogenes are indicated by red oblique lines (Cow TAAR pseudogenes are not shown). Mesh size, 10 kbp × 10 kbp.