Table 1.

Table of genes encoding for the critical regulator of Merkel cell formation in the back skin but not in the glabrous paw skin.

Gene Symbol(s)	Mouse models used to study the gene loss of function effects	Merkel Cell phenotype in the back skin	Merkel Cell phenotype in the glabrous skin
Shh	ShhEGFPcre/EGFPcre Krt14-Cre; Shhflox/flox	Merkel Cells are not formed (Perdigoto et al., 2016; Xiao et al., 2016)	Reduced number of Merkel Cells (Perdigoto et al., 2016)
Smo	Krt14-Cre; Smoflox/flox Krt5-tTA; TRE-Cre; Smoflox/flox	Merkel Cells are not formed (Perdigoto et al., 2016; Xiao et al., 2016)	Reduced number of Merkel Cells (Perdigoto et al., 2016)
Eed, Smo	Krt14-Cre; Eedflox/flox; Smoflox/flox	Reduced number of Merkel Cells (Perdigoto et al., 2016)	Increased number of Merkel Cells (Perdigoto et al., 2016)