Related Experiment Video

Updated: Jul 20, 2026

Profiling of Methyltransferases and Other S-adenosyl-L-homocysteine-binding Proteins by Capture Compound Mass Spectrometry (CCMS)
17:12

Profiling of Methyltransferases and Other S-adenosyl-L-homocysteine-binding Proteins by Capture Compound Mass Spectrometry (CCMS)

Published on: December 21, 2010

S-adenosylhomocysteine hydrolase deficiency in a 26-year-old man

N R M Buist1, B Glenn, O Vugrek

  • 1Departments of Pediatrics and Medical Genetics, Oregon Health & Science University, 8510 S.W. White Pine Lane, Portland, OR 97225, USA. Buistnrm@aol.com

Journal of Inherited Metabolic Disease
|June 1, 2006
PubMed

Insights

This study details the third human case of S-adenosylhomocysteine (AdoHcy) hydrolase deficiency, characterized by severe myopathy and developmental delays. The findings highlight the impact of enzyme deficiency on methylation processes and cellular function.

Area of Science:

  • Biochemistry
  • Genetics
  • Metabolic Disorders

Background:

  • S-adenosylhomocysteine (AdoHcy) hydrolase is crucial for regulating cellular methylation.
  • Deficiency in this enzyme is a rare genetic disorder with significant clinical manifestations.

Observation:

  • The third reported human case of AdoHcy hydrolase deficiency presented with severe myopathy, developmental delay, elevated creatine kinase, and hypermethioninaemia.
  • Diagnosis was confirmed at age 26 through enzyme activity assays and genetic mutation analysis.
  • The patient exhibited altered levels of phosphatidylcholine, free choline, and guanidinoacetate, suggesting methylation pathway disruption.

Findings:

  • Markedly elevated plasma AdoHcy and S-adenosylmethionine levels were observed.
  • Red blood cell AdoHcy hydrolase activity was significantly reduced (20% of control).
  • Two missense mutations in the AdoHcy hydrolase gene were identified.
  • Leukocyte DNA showed global hypermethylation compared to controls and parents.

Implications:

  • Elevated AdoHcy may inhibit methylation of phosphatidylethanolamine and guanidinoacetate.
  • The findings provide insights into the biochemical consequences of AdoHcy hydrolase deficiency.
  • This case expands understanding of a rare metabolic disorder and its impact on DNA methylation.

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