<unk>  is a rare genetic disorder that causes developmental delays and absent fifth finger and toe nails. There had been 31 reported cases by 1991. The number of occurrences since then has grown and is now reported to be around 80. The differential includes Nicolaides–Baraitser<unk> .
Coffin–Siris syndrome
Maroteaux–Lamy syndrome
Dunnigan familial partial lipodystrophy
Beckwith–Wiedemann syndrome
Laurence–Moon syndrome
Griscelli syndrome type 2
Qazi–Markouizos syndrome
Klüver–Bucy syndrome