A reciprocal translocation (1;15) (36.2;q24) in a neuroblastoma cell line is accompanied by DNA duplication and may signal the site of a putative tumor suppressor-gene.

Cytogenetic analyses and molecular deletion studies of human neuroblastomas have indicated the chromosomal bands 1p36.1-1p36.2 as a location of genetic information which may be involved in tumorigenesis. To define this putative neuroblastoma locus in more detail we have analysed cell lines with alterations of distal 1p. Here we show, by fluorescence in situ hybridization (FISH), that cell line NGP has a reciprocal 1;15 translocation. Loci D1S214/D1S96 could be shown to map telomeric/distal, D1S228 centromeric/proximal to the break. We have identified yeast artificial chromosomes (YACs) that cover the break and map to D1S160 and D1S244. This chromosomal position is within the smallest region of overlap (SRO) found in neuroblastoma tumors (Weith et al., 1989; Caron et al., 1993; Schleiermacher et al., 1994) and within the region of a constitutional interstitial deletion of a neuroblastoma patient (Biegel et al., 1993). Mapping studies with FISH revealed that the translocation is associated with duplication of DNA. It appears, as if the subchromosomal region we describe here is a good candidate for harboring the postulated neuroblastoma suppressor-gene.