Table 2.

Literature survey of the tissue-specific transcription of globin genes in different vertebrate species

Species	Tissue-specific expression	Reference
Zebrafish (Danio rerio)	GbX: highest levels in brain and eye; low levels in muscle, liver, heart, and gill	Blank et al. (2011b)
Zebrafish (Danio rerio) & Pufferfish (Tetraodon nigroviridis)	Cygb 1: highest levels in brain, heart, eye, gut; Cygb 2: highest levels in brain, eye (250–300 fold higher than Cygb1), Cygb2 is higher expressed than Cygb1 with exception of gut and gills	Fuchs et al. (2005)
Goldfish (Carassius auratus)	GbX: weak signals in gills, muscle, heart, gut, kidney, spleen, liver; no expression in brain, eye	Roesner et al. (2005)
African clawed frog (Xenopus laevis)	GbX: highest in eye, weak in ovary, brain, heart, liver, kidney; no expression in skeletal muscle Ngb: predominantly in eye, brain; weaker in gut, ovary, kidney; not expressed in liver, heart, and skeletal muscle Cygb: in all tissues, highest in brain, kidney, eye GbY: in all tissues, strongest in ovary, kidney, eye; only faint expression in skeletal muscle	Fuchs et al. (2006)
African clawed frog (Xenopus laevis)	Cygb: highest levels in heart and skeletal muscle, weak in liver and spleen	Xi et al. (2007)
Western clawed frog (Xenopus tropicalis)	Ngb: in eye, gut, ovary, no expression heart, liver GbX: in eye, brain, gut, heart, no expression in liver, ovary, skeletal muscle	Fuchs et al. (2006)
Chicken (Gallus gallus)	Cygb: in all tissues (brain, eye, muscle, liver, spleen, heart) Ngb: only in brain, eye GbE: only in eye	Kakhniashvili et al. (2004)