Abstract
Deletion of the short arm of chromosome I is among the most recurrent cytogenetic alterations found in neuroblastoma and has been associated with short survival. However, this prognostic information, which relies on timeโconsuming techniques, is not yet routinely exploited. In order to set up a reliable and simple routine test to determine Ip deletion in neuroblastoma, we have used the polymerase chain reaction to genotype neuroblastoma DNA at 2 loci containing a variable number of tandem repeats and located on the distal part of the short arm of chromosome I. Agarose gel electrophoresis and ethidium bromide staining of the amplification products enable a simple determination of constitutional and tumor genotypes at these loci to be made. A total of 37 samples from 29 patients were studied with this technique. Loss of heterozygosity (LOH) could be identified in 8 cases. In each case the results obtained were in agreement with those achieved by the Southern procedure. This technique will be of particular interest in the pretherapeutic analysis of Ip deletions in small tumor samples obtained by fineโneedle aspirates of the primary tumor. It should also enable retrospective studies from paraffinโembedded tumor fragments to be made and provide information for the analysis of tumor heterogeneity in neuroblastoma and in other tumors with Ip deletions. ยฉ 1992 WileyโLiss, Inc.