NEURAL-TUBE DEFECTS AND DELETIONS OF 22Q11

Recently we reported on three unrelated children with neural tube defe cts (NTDs) and deletion of 22q11. Two of these children have velo-card io-facial syndrome and the third DiGeorge sequence. Thus, NTDs appear to be part of the clinical picture due to 22q11 deletion. To further e xplore this association and to clarify what findings should prompt tes ting for this deletion in individuals with NTDs, we have reviewed all patients in a large regional spina bifida clinic population. Two hundr ed ninety-five patients with NTDs were identified by chart review, Cha rts were reviewed for congenital heart defect, minor facial anomalies, thymic hypoplasia, cleft lip and/or palate, hypocalcemia, and a famil y history of a NTD, congenital heart defect, or cleft lip and/or palat e. A total of 22 patients was identified with NTD and at least one mor e clinical trait and/or a positive family history. Sixteen children re ceived cytogenetic and molecular testing including the three previousl y reported patients diagnosed with a 22q11 deletion. Results of cytoge netic and molecular studies of the remaining 13 patients were normal. Deletion of 22q11 is an infrequent cause of NTDs. We recommend testing for the 22q11 deletion in patients with a NTD and conotruncal heart d efect. Testing should be considered in patients with a NTD who have a first degree relative with a conotruncal heart defect or have addition al clinical findings of VCFS or DGS. (C) 1996 Wiley-Liss, Inc.