Deletions of the short arm of chromosome 1 (1p) are frequent alterations in neuroblastoma. Although a consensus region of deletion has been mapped to chromosome subband 1p36, recent studies suggest that several distinct loci on this chromosome may be involved in neuroblastoma. Moreover, different patterns of deletion might be associated with different clinical and biological characteristics of the tumours. These findings emphasise the importance of assessing the localisation and the extent of the deletions in neuroblastoma. We developed a technique which allows analysis of loss of heterozygosity at multiple loci on 1p in a single step, making use of a multiplex PCR method. Primers specific for six microsatellite loci mapped in the different regions of interest on 1p were used for simultaneous amplification of DNA, and loss of heterozygosity was determined after separation of the alleles by denaturing polyacrylamide gel electrophoresis. This technique enables a simple analysis of the position and extent of 1p deletions, and can be used for routine evaluation of 1p status in neuroblastoma.