POSSIBLE NEW VARIANT OF NIJMEGEN BREAKAGE SYNDROME

We report on a child with microcephaly, small facial and body size, an d immune deficiency. The phenotype is consistent with Nijmegen breakag e syndrome (NBS), with additional clinical manifestations and laborato ry findings not reported heretofore. Most investigations, including th e results of radiation-resistant DNA synthesis, concurred with the dia gnosis of NBS. Cytogenetic analysis documented abnormalities in virtua lly all cells examined. Along with the high frequency of breaks and re arrangements of chromosomes 7 and 14, we found breakage and monosomies involving numerous other chromosomes. Because of some variation in th e clinical presentation and some unusual cytogenetic findings, we sugg est that our patient may represent a new variant of Nijmegen breakage syndrome. (C) 1996 Wiley-Liss, Inc.