Radial ray defects, renal ectopia, duodenal atresia and hydrocephalus: the extended spectrum for Fanconi anaemia.

We present two families with a striking concordance of multiple anomalies. These include duodenal and other bowel atresia, radial ray defects especially absent or vestigial thumb, renal ectopia and hydrocephalus. The presence of diagnostically raised sensitivity to mitomycin C in the first family has confirmed Fanconi anaemia. This has further increased the spectrum of abnormalities in Fanconi anaemia and highlights the importance of mitomycin C analysis if elements of this spectrum are encountered.