We have constructed a YAC contig containing 54 clones and a minimum of 7 Mbp of human DNA, that maps to bands q34-35 on chromosome 5. The contig was nucleated using FISH mapped cosmid clones shown to flank the t(2;5)(p23;q35) translocation breakpoint in a CD30-positive large cell lymphoma cell line. Thirty of the 54 YAC clones are non-chimeric and six span the translocation breakpoint, as determined by FISH analysis. A total of 28 YAC clone end fragments, 14 non-polymorphic YAC end STS probes and 13 polymorphic microsatellite STS markers have been used to order clones within the contig. The most distal genetic markers (D5S498 and D5S619) are separated by 15 cM based on multipoint linkage analysis. This map of overlapping clones and the set of densely spaced physical markers will promote our understanding of the 5q34-35 region and its associated genes.