The human PLZF (promyelocytic leukaemia zinc finger) gene encodes a Krüppel-like zinc finger protein, which was identified via the reciprocal translocation t(11;17)(q23;q21) fusing it to the retinoic acid receptor alpha (RARalpha) gene in promyelocytic leukaemia. To determine its complete genomic organisation, we constructed a cosmid-map fully containing the hPLZF gene. The gene has seven exons, including a novel 5' untranslated exon, varying in size from 87 to 1358bp and spans at least 120kb. Flanking intronic sequences were identified and all splice acceptor and donor sites conformed to the gt/ag rule. Five polymorphic markers could be fine located in its vicinity. These data will facilitate mutation analysis of hPLZF in t(11;17) leukaemia cases, as well as assist mapping and loss-of-heterozygosity analysis. Here we have tested hPLZF as a possible candidate for the PGL1 locus involved in hereditary head and neck paragangliomas. However, mutation analysis revealed no aberration in 12 paraganglioma patients from different families.