UNRAVELING THE MYSTERY: DOPA RESPONSIVE DYSTONIA DUE TO GTP CYCLOHYDROLASE-1 DEFICIENCY CAUSED BY PTS GENE MUTATION
Dr Durgesh Agarwal , Assistant Professor, Department of Paediatrics, Grant Government Medical College and Sir J.J Group Of Hospitals Mumbai, IndiaAbstract
Dopa-responsive dystonia (DRD) is a rare neurological disorder characterized by progressive dystonia that responds dramatically to levodopa treatment. In some cases, DRD is caused by mutations in the GTP cyclohydrolase-1 (GCH1) gene, leading to GTP cyclohydrolase-1 deficiency. However, a subset of DRD cases can also be attributed to mutations in the PTS gene, which encodes 6-pyruvoyl-tetrahydropterin synthase, an enzyme involved in the biosynthesis of tetrahydrobiopterin (BH4). This study aims to unravel the mystery of DOPA responsive dystonia due to GTP cyclohydrolase-1 deficiency caused by PTS gene mutation. We present a case report of a patient with DRD, where whole-exome sequencing revealed a novel PTS gene mutation. Through this investigation, we shed light on the pathogenesis and genetic basis of this rare form of DRD, providing insights that may lead to improved diagnosis, treatment, and genetic counseling for affected individuals.
Keywords
Dopa-responsive dystonia, GTP cyclohydrolase-1 deficiency, PTS gene mutation
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