/ (ˌhəʊməʊˈsɪstiːn) /


an amino acid occurring as an intermediate in the metabolism of methionine. Elevated levels in the blood may indicate increased risk of cardiovascular disease

Nearby words

  1. homochrome,
  2. homochromous,
  3. homochronous,
  4. homocladic anastomosis,
  5. homocyclic,
  6. homocystine,
  7. homocystinemia,
  8. homocystinuria,
  9. homocytotropic,
  10. homocytotropic antibody

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Medicine definitions for homocysteine


[ hō′mə-sĭstə-ēn′, -ĭn, -tē- ]


An amino acid that is a homologue of cysteine, is produced by the demethylation of methionine, and forms a complex with serine that metabolizes to produce cysteine and homoserine.

The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Science definitions for homocysteine


[ hō′mə-sĭstə-ēn′, -ĭn, -tē- ]

An amino acid used normally by the body in cellular metabolism and the manufacture of proteins. Elevated concentrations in the blood are thought to increase the risk for heart disease by damaging the lining of blood vessels and increasing the risk of blood clot formation. High homocysteine levels are associated with certain vitamin deficiencies and metabolic disorders. Chemical formula: C4H9NO2S.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.