CDKN1C and Silver-Russell syndrome: In contrast, for several other genes (e.g., FGFR3 and NSD1) a loss of function is associated with tall stature (CATSHL syndrome and Sotos syndrome, respectively), and gain of function with short stature (FGFR3 and CDKN1C; Achondroplasia and Silver-Russell syndrome) (2).