Hexosaminidase A Percent and Total Hexosaminidase in Leukocytes
Ordering Recommendation
Preferred test to diagnose or identify carriers of Tay Sachs disease, especially in individuals who are pregnant, use oral contraceptives, have severe liver or autoimmune disease, or had previously inconclusive Hexosaminidase A testing in plasma/serum.
Quantitative Fluorometry
2-9 days
New York DOH Approval Status
This test is New York DOH approved.
Specimen Required
Patient Preparation
Yellow (ACD).  
Specimen Preparation
Do not transfer whole blood to other containers. Transport 3 mL whole blood. (Min: 1.0 mL)  
Storage/Transport Temperature
Room temperature. Also acceptable: Refrigerated.  
Unacceptable Conditions
Whole blood received greater than 3 days from collection. Grossly hemolyzed specimens.  
Clinical information is needed for appropriate interpretation. Additional required information includes age, gender, diet (e.g.TPN therapy), drug therapy, and family history. Biochemical Genetics Patient History Form is available on the ARUP Web site at http://www.aruplab.com/patienthistory or by contacting ARUP Client Services.  
Ambient: 3 days; Refrigerated: 3 days; Frozen: Unacceptable  
Reference Interval
Effective November 18, 2013

Greater than or equal to 63 percent
Interpretive Data
Refer to report.
This test is used for the diagnosis of Tay-Sachs disease and can also be used to identify carriers for this disorder. Carrier screening is offered to individuals of Ashkenazi Jewish descent because of the high incidence of the disease in this population.
CPT Code(s)
Component Test Code*Component Chart Name
2008126Hexosaminidase A Percent in Leukocytes
2008127Hexosaminidase Total, Leukocytes
2008128Hexosaminidase in Leukocytes Interp
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.
Cross References
  • HEXA enzyme testing
  • Hexosaminidase A and Total, leukocytes