“…In dfna5 morphants and jekyll ( ugdh ) mutants, HA fails to be produced, and projection outgrowth is blocked (Neuhauss et al, 1996; Busch-Nentwich et al, 2004). Variable projection outgrowth defects in the zebrafish ear have also been reported after knockdown or mutation of ncs1a (Blasiole et al, 2005), atrophin2 ( rerea - Zebrafish Information Network), fgf8a (Asai et al, 2006), cdh2 (Babb-Clendenon et al, 2006), atp1a1a.2 (Blasiole et al, 2006), atp2b1a (Cruz et al, 2009) and grhl2 (Han et al, 2011), and in Hedgehog pathway mutants (Hammond et al, 2010). …”