Seven novel mutations in the ORNT1 gene (SLC25A15) in patients with hyperornithinemia, hyperammonemia, and homocitrullinuria syndrome

@article{Salvi2001SevenNM,
  title={Seven novel mutations in the ORNT1 gene (SLC25A15) in patients with hyperornithinemia, hyperammonemia, and homocitrullinuria syndrome},
  author={Sergio Salvi and Carlo Dionisi-Vici and Enrico Bertini and Margherita Verardo and F M Santorelli},
  journal={Human Mutation},
  year={2001},
  volume={18}
}
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 (Q89X, G27R, G190D, R275Q, c.861insG, c.164insA, and IVS5+1G→A). Other previously described variants were a heterozygous deletion of a phenylalanine residue (F188del) in one allele and the R179X in two. The G27R mutation was carried by two patients. Analyses of ORNT1 mRNA in four patients showed… 
Identification of novel mutations in the SLC25A15 gene in hyperornithinemia‐hyperammonemia‐homocitrullinuria (HHH) syndrome: A clinical, molecular, and functional study
TLDR
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.
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TLDR
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TLDR
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TLDR
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TLDR
The clinical phenotype of HHH syndrome is extremely variable and its severity does not correlate with the genotype or with recorded ammonium/ornithine plasma levels, suggesting the need for a better understanding of the still unsolved pathophysiology of the disease.
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TLDR
All the mitochondrial carrier-related diseases known until now are reviewed, focusing on the connections between the molecular basis, altered metabolism, and phenotypes of these inherited disorders.
Determination of homocitrulline in urine of patients with HHH syndrome by liquid chromatography tandem mass spectrometry
TLDR
The current method solves specificity issues in homocitrulline determination often encountered with some ninhydrin-based systems (coelution with methionine) and some o-phthalaldehyde-based ones (coalution with taurine), and presents an attractive alternative with a relatively high throughput.
Role of early management of hyperornithinaemia‐hyperammonaemia‐homocitrullinuria syndrome in pregnancy
TLDR
In addition to the absent fetal corpus callosum observed in this case, other fetal cerebral abnormalities, including speech delay and intellectual impairment, have been recognised and demonstrate the importance of timely intervention by a metabolic dietician and dietary compliance in the early organogenesis stage of pregnancy.
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