Others studies have reported mutations in AXIN2 (HED), CDH1 (blepharocheilodontic syndrome), DSP (Carvajal/Naxos syndrome), EDARADD (HED), EVC2 (EVCS), FGFR2 (Beare–Stevenson syndrome), PCNT (microcephalic osteofysplastic dwarfism type 2), PITX2 (ARS), PTCH1 (basal cell nevus syndrome), IKBKG (incontinentia pigmenti), LEF1 (HED), MSX1 (Witkop’s syndrome), NPHP1 (juvenile nephronophtisis), SRCAP (Floating-Harbor syndrome), and TBCE (Sanjad–Sakati syndrome). This evidence concerns the gene PTCH1 and hypohidrotic ectodermal dysplasia.