<unk>  is an autosomal recessive neurological<unk>  that results in the over-accumulation of phytanic acid in cells and tissues. It is one of several disorders named after Norwegian neurologist Sigvald Bernhard<unk>  (1907–1991).<unk>  typically is adolescent onset and is diagnosed by above average levels of phytanic acid. Humans obtain the necessary phytanic acid primarily through diet. It is still unclear what function phytanic acid plays physiologically in humans, but has been found to regulate fatty acid metabolism in the liver of mice.
Refsum disease
Shell nail syndrome
Arthritis mutilans
Fuchs' dystrophy
Dentinogenesis imperfecta
Scleroderma
Chyloderma
Xeroderma