Southern blot hybridization of notothenioid genomic DNA with 32P-labeled N. coriiceps Mb cDNA. Genomic DNA isolated from N. coriiceps (lane 1), G. gibberifrons (lane 2), C. rastrospinosus (lane 3), C. gunnari (lane 4), P. macropterus (lane 5), and C. aceratus (lane 6) were digested with HindIII, resolved by electrophoresis though a 0.7% agarose gel, and hybridized with the random-primed Mb cDNA probe. Mobility of molecular size markers is shown at right.