A novel nonsense mutation of the GTP cyclohydrolase I gene in a family with dopa-responsive dystonia

We report a new nonsense mutation in the GTP cyclohydrolase I (GCH1) gene i n a family with dopa-responsive dystonia. Two sisters and three children of the sisters are affected. The exons of the GCH1 gene were amplified by PCR and sequenced. The substitution of thymine for cytosine at nucleotide posi tion 142 causing a nonsense mutation (Q48X) in exon 1 was identified in all of the five affected patients. There were three asymptomatic carriers of t he mutation in the family. Copyright (C) 2001 S. Karger AG, Basel.