Two new mutations of the ADAR1 gene associated with dyschromatosis symmetrica hereditaria.

Dyschromatosis symmetrica hereditaria (DSH) is a pigmentary genodermatosis of autosomal dominant inheritance characterized by a mixture of hyperpigmented and hypopigmented macules distributed on the dorsal aspects of the hands and feet. Genetic studies have identified mutations in ADAR1 gene to be responsible for this disorder. We detected two mutations in two families with DSH, which include a heterozygous g-->a transversion at the first base of the 3'-acceptor splice site of intron 5 (c. 2080-1g>a, IVS5-1g>a) and a transition c.3076C>T. IVS5-1g>a should prevent proper splicing of the transcript while c.3076C>T leading to a missense mutation p.R1026W of the ADAR1 gene. Our study suggests that splice site mutation IVS5-1g>a and missense mutation p.R1026W are new mutations of ADAR1 gene, which should be useful in genetic counseling and prenatal diagnosis for the affected families and expanding the database on ADAR1 gene mutations in DSH.