The nucleotide sequence encoding the human 78 kDa gastrin binding protein (GBP) has been deduced from overlapping fragments generated by the polymerase chain reaction with oligonucleotides based on the sequence of the porcine GBP (Mantamadiotis, T. et al. (1993) Biochim. Biophys. Acta 1170, 211-215) and cDNA from the colonic carcinoma cell line LIM 1215 as template. The mature human GBP is 90% identical to the porcine GBP. Clones encoding the human GBP gene, which contains 19 exons, have been isolated from human genomic libraries. The positions of the exon/intron junctions are completely different from the junctions in the gene encoding the related peroxisomal trifunctional enzyme. Clones encoding a related pseudogene have also been isolated and sequenced.