Test Catalog

Test ID: HCYSP    
Homocysteine, Total, Plasma

Useful For Suggests clinical disorders or settings where the test may be helpful

An aid for screening patients suspected of having an inherited disorder of methionine metabolism including:

-Cystathionine beta-synthase deficiency (homocystinuria)

-Methylenetetrahydrofolate reductase deficiency (MTHFR) and its thermolabile variants

-Methionine synthase deficiency

-Cobalamin (Cbl) metabolism

-Combined methyl-Cbl and adenosyl-Cbl deficiencies: Cbl C2, Cbl D2, and Cbl F3 deficiencies

-Methyl-Cbl specific deficiencies: Cbl D-Var1, Cbl E, and Cbl G deficiencies

-Transcobalamin II deficiency

-Adenosylhomocysteinase (AHCY) deficiency

-Glycine N-methyltransferase (GNMT) deficiency

-Methionine adenosyltransferase (MAT) I/III deficiency


Screening and monitoring patients suspected of or confirmed with an inherited disorder of methionine metabolism


Evaluating individuals with suspected deficiency of vitamin B12 or folate

Method Name A short description of the method used to perform the test

Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)

NY State Available Indicates the status of NY State approval and if the test is orderable for NY State clients.


Reporting Name Lists a shorter or abbreviated version of the Published Name for a test

Homocysteine, Total, P

Aliases Lists additional common names for a test, as an aid in searching

Cystathionine beta-synthase deficiency
Methylenetetrahydrofolate reductase deficiency (MTHFR)
MTHFR deficiency
Methionine synthase deficiency
Cobalamin (Cbl) metabolism
Methyl-Cobalamin deficiency
Adenosyl-cobalamin deficiency
Cbl C2 deficiency
Cbl D2 deficiency
Cbl F3 deficiency
Cbl D-Var1 deficiency
Cbl E deficiency
Cbl G deficiency
Transcobalamin II deficiency
Adenosylhomocysteinase (AHCY) deficiency
Glycine N-methyltransferase (GNMT) deficiency
Methionine adenosyltransferase (MAT) I/III deficiency
Cobalamin C2 deficiencyCobalamin D2 deficiency
Cobalamin F3 deficiency
Cobalamin D-Variant 1 deficiency
Cobalamin E deficiency
Cobalamin G deficiency