<unk>  is an autosomal recessive peroxisomal disorder caused by absent or very low levels of the enzyme catalase. Catalase breaks down hydrogen peroxide in cells into water and oxygen. Low levels of catalase can cause hydrogen peroxide to build up, causing damage to cells.
Acatalasia
Oral galvanism
Onychotillomania
Amaurosis fugax
Distichia
Pellagra
Anotia
Bruxism