ABSTRACT
The porphyrias are diseases caused by defective biosynthesis of heme. Leavened by
digressions on porphyria trivia, this article presents selected highlights from the
last 15 years of research on the chemistry, diagnosis, and treatment of the porphyrias.
Thanks largely to genetic analysis and new light shed on the magical chemistry of
heme biosynthesis, this period has seen great advances in the understanding of porphyria.
Sequence analyses of the genes for all of the enzymes required for heme biosynthesis
have revealed the porphyrias as highly heterogeneous, with multiple mutations underlying
each type. As a result of technical advances, clinical porphyrin analyses are easier
and more detailed, but their misapplication to “multiple chemical sensitivity syndrome”
or “intoxication porphyria” is unfortunate. The prospect of gene therapy shines ever
brighter but is neither safe nor effective enough to be considered for porphyria.
As practical spin-offs, porphyrins are in use increasingly for diagnosis and treatment
of cancer and as herbicides and pesticides. Accounts of alleged porphyria in “Prominent
People” in the popular press continue to appear, generating fanciful misconceptions,
often at the expense of patients with these fascinating diseases.
KEY WORDS
inborn errors of metabolism - porphyrin - porphyrinuria - photodynamic therapy
