In 10 (19%) of the formerly 53 candidate genes an association to a NDD was meanwhile published (GRM7, EZR, EDC3, EEF1D, TMTC3, GALNT2, SLC44A1, PTRHD1, TMEM94, NCAPD2; File S2). This evidence concerns the gene PTRHD1 and Neurodevelopmental delay.