About two thirds of cases are associated with other congenital disorders, including Adams-Oliver syndrome (aplasia cutis congenita with partial aplasia of the skull bones and terminal transverse limb malformations), Holt-Oram syndrome, TAR (t hrombocytopenia - a bsent r adius) syndrome, Fanconi anemia, and VACTERL (v ertebral anomalies, a nal atresia, c ardiac malformations, t racheo e sophageal fistula, r enal anomalies and r adial aplasia, and l imb anomalies) syndrome.