A human "epidermal-type" 12-lipoxygenase (e-12LO) pseudogene was cloned using a murine e-12LO cDNA probe. Similar to other lipoxygenase genes, the genomic sequence revealed 14 exons and 13 introns covering 6.7 kb of DNA. cDNA corresponding to this gene was amplified from RNA of human skin and hair follicles by RACE-PCR and displayed 65-80% identity to the three murine 12-lipoxygenase cDNAs. Based on several criteria, humans appear to lack a functional e-12LO gene but instead have acquired an expressed pseudogene. The pseudogene designated ALOX12P2 was localized to chromosome 17p13 by analysis of somatic hybrid DNA panels.