Protoporphyrinogen oxidase: complete genomic sequence and polymorphisms in the human gene.

Variegate porphyria (VP) is an autosomal dominant disorder of heme synthesis caused by a partial deficiency of protoporphyrinogen oxidase (PPOX). Human cDNA encoding PPOX has been recently sequenced and the gene has been cloned, assigned to chromosome 1q23, and its exon/intron organization has been characterized. We report here the complete nucleotide sequence of the Human PPOX gene. Including 660 bp of its promotor region, the PPOX gene spans 5.5 kb. Introns vary in size from 84 bp to 507 bp. Two exonic and 3 intronic biallelic sequence variations have been characterized.