For example, alterations of fur color [31], muscular disorders [32,33] and body size diversity [34,35] in Canidae are correlated with SINE insertions associated respectively with SILV, PTPLA and IGF1. In addition, SINE insertion into an exon of STK38L causes retinal degeneration [36] and an ancient SINE locus serves as an enhancer for fibroblast growth factor 8 (Fgf8) during mammalian brain formation [37]. Here, FGF8 is linked to retinal degeneration.