For example, rod cells have been found to be central to the pathogenesis of FDM in Gnat1 gene knockout mice [39], while in myopia patients, alterations in photoreceptor density were found using an ocular imaging technique as reduced rod and cone ratio [40], and reduced astrocyte count [41], while functional electroretinogram (ERG) recording indicated an association of the rod system function with the progression of myopia [42]. Here, GNAT1 is linked to myopia.