Fuhrmann syndrome and Al-Awadi/Raas-Rothschild/Schinzel (AA/RRS) phocomelia syndrome are rare autosomal recessive inherited disorders characterized by aplastic/hypoplastic nails with ectopic dorsal palms, absence of humeri, hypoplastic ulnae, and bowed short radii with the elbow joints present, shown to result from missense mutations in WNT7A (p.Ala109Thr and p.Arg292Cys).
Mutations of the human helicase gene RECQL4 have been identified in a subset of patients with Rothmund-Thomson syndrome (RTS) and in children with the diagnosis of RAPADILINO syndrome (RAdial hypoplasia/aplasia, PAtellar hypoplasia/aplasia, cleft or highly arched PAlate, DIarrhea and DIslocated joints, LIttle size [>2 SDs below the mean in height] and LImb malformation, and slender NOse and NOrmal intelligence).