Dyschromatosis symmetrica hereditaria

Dyschromatosis symmetrica hereditaria, also known as reticulate acropigmentation of Dohi and as symmetrical dyschromatosis of the extremities, is a rare autosomally inherited skin disease. It is characterized by progressively pigmented and depigmented macules, often mixed in a reticulate pattern, that are concentrated on the dorsal extremities. The disease was first reported in Japan but has also been found in people from Europe, India and the Caribbean. It is caused by mutation in the ADAR1 gene, which codes for the double stranded RNA specific adenosine deaminase and lies on the long arm of chromosome 1 at 1q21. Diagnosis is made by visual examination of the skin together with a skin biopsy.