CDKN1C is implicated in syndromes associated with intrauterine growth restriction (IUGR) (IMAGE syndrome) (26) and over-growth (Beckwith-Wiedemann syndrome) (27); one of the birth weight SNPs is located 47 146 bp from this gene within an intron of KCNQ1, which is not linked to DDs. This evidence concerns the gene KCNQ1 and Beckwith-Wiedemann syndrome.