Diagnosis of Japanese patients with HHH syndrome by molecular genetic analysis: a common mutation, R179X

  title={Diagnosis of Japanese patients with HHH syndrome by molecular genetic analysis: a common mutation, R179X},
  author={Takeshi Miyamoto and Naomi Kanazawa and Shigeo Kato and M. Kawakami and Yoshito Inoue and Tomiko Kuhara and Takehiko Inoue and Kenzo Takeshita and Seiichi Tsujino},
  journal={Journal of Human Genetics},
AbstractPatients with mitochondrial ornithine transporter deficiency (or HHH syndrome) present with various neurological symptoms, including mental retardation, spastic paraparesis with pyramidal signs, cerebellar ataxia, and episodic disturbance of consciousness or coma due to hyperammonemia. We previously described three novel mutations in the ORNT1 gene in Japanese patients with HHH syndrome. In this article, we report a new patient with HHH syndrome, a 52-year-old woman, who had the typical… 
A novel mutation, P126R, in a Japanese patient with HHH syndrome.
A novel R275X mutation of the SLC25A15 gene in a Japanese patient with the HHH syndrome
Long-term follow-up of four patients affected by HHH syndrome.
Phenotypic variability among patients with hyperornithinaemia–hyperammonaemia–homocitrullinuria syndrome homozygous for the delF188 mutation in SLC25A15
Long-term follow-up showed that variable intellectual impairment and lower limb spasticity often occur, together or separately, with no obvious relationship to age at diagnosis and compliance with treatment, and the need to better understand the pathophysiology of HHH is emphasised.
Seven novel mutations in the ORNT1 gene (SLC25A15) in patients with hyperornithinemia, hyperammonemia, and homocitrullinuria syndrome
Eight unrelated Italian patients with the hyperornithinemia, hyperammonemia, and homocitrullinuria (HHH) syndrome were analyzed for mutations in the ORNT1 gene. Seven novel mutations were identified
Diagnosis and high incidence of hyperornithinemia-hyperammonemia-homocitrullinemia (HHH) syndrome in northern Saskatchewan
It was determined that ornithine levels, by tandem mass spectrometry, were not abnormal in newborns with F188Δ mutation, carriers and normals, and that newborn screening for HHH Syndrome in this high risk population is only possible by detection of the mutant allele using DNA analysis.
Identification of novel mutations in the SLC25A15 gene in hyperornithinemia‐hyperammonemia‐homocitrullinuria (HHH) syndrome: A clinical, molecular, and functional study
Although patient metabolic alterations responded well to low‐protein therapy, predictions concerning the long‐term evolution of HHH syndrome remain uncertain and the preference for a hepatic rather than a neurological presentation at onset continues to elude us.
Reversible Leukoencephalopathy in a Man with Childhood-onset Hyperornithinemia-Hyperammonemia-Homocitrullinuria Syndrome
Lukoencephalopathy in HHH syndrome may be reversible with the resolution of hyperammonemia-induced glutamine toxicity, and the administration of L-arginine and lactulose with a decrease in plasma ammonia levels and glutamine-glutamate peak on magnetic resonance spectroscopy.


Three novel mutations (G27E, insAAC, R179X) in the ORNT1 gene of Japanese patients with hyperornithinemia, hyperammonemia, and homocitrullinuria syndrome
This study confirms that defects in the ORNT1 gene cause the HHH syndrome and that the genetic basis in Japanese patients is heterogeneous, and reports three novel mutations in the mitochondrial ornithine transporter gene (ORNT1).
Hyperornithinemia, hyperammonemia, and homocitrullinuria. A new disorder of amino acid metabolism associated with myoclonic seizures and mental retardation.
There are several instances in which a low protein diet simultaneously caused clinical improvement and reduction or elimination of hyperammonemia.
Hyperornithinaemia-hyperammonaemia-homocitrullinuria syndrome is caused by mutations in a gene encoding a mitochondrial ornithine transporter
The results show that ORNT1 encodes the mitochondrial ornithine transporter involved in UC function and is defective in HHH syndrome.
The hyperornithinemia
  • 1995
Genotype and phenotype findings in the hyperornithinemia-hyperammonemia-homocitrullinuria (HHH) syndrome
  • J Inherit Metab Dis
  • 2000