A NOVEL MUTATION OF COPROPORPHYRINOGEN OXIDASE (CPO) GENE IN A JAPANESE FAMILY

Hereditary coproporphyria (HCP) is an autosomal dominant disease chara cterized by a deficiency of coproporphyrinogen oxidase (CPO). Only 11 mutations of the gene have been reported to date as the mutations resp onsible for HCP. We report here a novel mutation of the gene responsib le for the disease in a Japanese family. Analysis of the polymerase ch ain reaction (PCR) amplified DNA fragments of the gene by direct-seque ncing and/or cloning-based sequencing methods revealed the gene abnorm ality responsible for the disease. The mutation found was a single bas e deletion of T at nt position 526, which results in frame shift and t runcation of coded protein at amino acid position 204. Screening of pr e-symptomatic cases seemed to be possible by PCR restriction analysis using restriction enzyme Xcm I.