PTAR1 and congenital stationary night blindness: A number of genes listed in Additional file 2 are associated with the following traits in horses: joint and hoof health (ADAMTS3 [29]), leopard spotting coat patterns and congenital stationary night blindness (TRPM1 [30–31]), number of hair whorls on the face (PTAR1 [32]), gait patterns (the “gait keeper” gene DMRT3 [33–35]), and brown coat colour (TYRP1 [36–38]).