HOMOCYSTEINE LEVEL THIS BLOOD TEST MEASURES THE AMOUNT OF AMINO ACID HOMOCYSTEINE IN THE BLOOD. HOMOCYSTEINE LEVEL ALSO SCREENS PATIENTS WHO MAY BE AT HIGH RISK FOR HEAT DISEASE, BLOOD CLOTS, STROKE, DEEP VEIN THROMBOSIS, CORONARY ARTERY DISEASE. THE PRODUCTION OF HOMOCYSTEINE IN THE BODY IS PART OF A COMPLEX SYSTEM RELATED TO THE METABOLISM OF DIETARY PROTEIN.