“…However, evidence of colocalization of 5S and 18S rDNA has been reported for some species of Acipenseriformes (Fontana et al, 2003), Salmoniformes (e.g., Pendas et al, 1994;Moran et al, 1996;Fujiwara et al, 1998;Rossi & Gornung, 2005), Cypriniformes (Inafuku et al, 2000), Characiformes (e.g., Almeida-Toledo et al, 2002;Cioffi et al, 2009;Diniz et al, 2009 and references therein), Perciformes (Nirchio et al, 2009;Pisano & Ghigliotti, 2009) and, now also, Mugiliformes (present study). Interestingly, all the possible syntenic conditions have been found, either the two sets of genes in distinct and disjoint chromosomal regions, as in Astyanax scabripinnis (Mantovani et al, 2005) and Parodon tortuosus (=Parodon nasus) (Vicente et al, 2001), or in adjacent regions, as in M. incilis (present study) and Triportheus nematurus (Diniz et al, 2009), or the 5S rRNA genes interspersed along the clusters of 45S rDNA, as in Notothenioidei (Pisano & Ghigliotti, 2009).…”