WNT10A and Schöpf-Schulz-Passarge syndrome: First mutations in WNT10A were identified in patients with another ectodermal dysplasia, recessive odonto-onycho-dermal dysplasia (OODD, OMIM 257980), and an allelic disease Schöpf-Schulz-Passarge syndrome (SSPS, OMIM 224750), and most recently homozygous and heterozygous mutations have been identified in patients with isolated tooth agenesis [17–19,21,22].