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Updated: May 8, 2026
06:41
In Vivo Functional Study of Disease-associated Rare Human Variants Using Drosophila
Published on: August 20, 2019
A novel compound heterozygous tyrosine hydroxylase mutation (p.R441P) with complex phenotype
Kristoffer Haugarvoll1, Laurence A Bindoff
1Department of Neurology, Haukeland University Hospital, Bergen, Norway. haugarvoll@gmail.com
Journal of Parkinson'S Disease
|August 14, 2013
Summary
Tyrosine hydroxylase (TH) deficiency, caused by TH gene mutations, can lead to severe neurological disorders. Early diagnosis and treatment are crucial for managing this treatable condition.
Area of Science:
- Biochemistry
- Genetics
- Neuroscience
Background:
- Tyrosine hydroxylase (TH) is a critical enzyme in dopamine biosynthesis, dependent on tetrahydrobiopterin (BH4).
- Mutations in the TH gene are linked to autosomal recessive disorders, including dopa-responsive dystonia (DRD) and infantile encephalopathy.
Observation:
- A patient with TH-deficiency presented with compound heterozygous missense mutations in the TH gene.
- One identified mutation, p.R441P, was novel.
Findings:
- The study details a case of TH-deficiency resulting from compound heterozygous TH gene mutations.
- Clinical insights into TH-deficiency phenotypes and diagnostic approaches are provided.
Implications:
- Timely diagnosis of TH-deficiency is essential for effective treatment and improved patient outcomes.
- Understanding TH gene mutations aids in diagnosing and managing related neurological disorders.
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