<unk> s are a group of inherited or acquired disorders of certain enzymes in the heme biosynthetic pathway (also called<unk>  pathway). They are broadly classified as hepatic<unk> s or erythropoietic<unk> s, based on the site of the overproduction and mainly accumulation of the<unk> s (or their chemical precursors). They manifest with either skin problems or with neurological complications (or occasionally both).
Porphyria
Chalicosis
Albinism
Xanthinuria
Scurvy
Acute intermittent porphyria
Trimethylaminuria
Prurigo nodularis