At the moment, four different genes are known to cause COFS syndrome: ERCC6 (COFS1, MIM #214150), ERCC2 (COFS2, MIM #610756), ERCC5 (COFS3, MIM #616570), and ERCC1 (COFS4, MIM #610758) [3, 4]. Here, ERCC1 is linked to COFS syndrome.