Dyschromatosis symmetrica hereditaria

Dyschromatosis symmetrica hereditaria (also known as "reticulate acropigmentation of Dohi", and "symmetrical dyschromatosis of the extremities") is a rare autosomally inherited dermatosis. It is characterized by progressively pigmented and depigmented macules, often mixed in a reticulate pattern, concentrated on the dorsal extremities. It was first reported in Japan, but has also been found to affect individuals from Europe, India and the Caribbean.

Genetics
This disease is caused by mutation in the double stranded RNA specific adenosine deaminase (ADAR1) gene. This gene is located on the long arm of chromosome 1 (1q21).

Diagnosis
Diagnosis is by visualisation and skin biopsy.