Homocysteine is an amino acid.In the body homocysteine is converted to cysteine by vitamin B6 or is returned to methionine where Vitamin B12 plays a role. Cysteine is important for the body. By any case if homocysteine is not converted to cysteine or returned to methionine then its levels increase in the body. The increased levels are associated with heart attack(Myocardial infarction), stroke, blood clot formation and maybe the development of Alzheimer’s disease.


This test is suggested in case of:

  • Vitamin B12 and/or folate deficiency
  • Assessing a person’s risk of cardiovascular disease
  • After a heart attack or stroke to help guide treatment
  • If newborn screening spots an elevated level of methionine or if an infant or child has signs and symptoms of homocystinuria