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Laboratory Medicine

Test catalogue

Tay-Sachs Enzyme Screening (TSD, B-Hexosaminidase A deficiency, HEXA deficiency)

Test Name

Tay-Sachs Enzyme Screening (TSD, B-Hexosaminidase A deficiency, HEXA deficiency)

Green Tube Red Tube with thin top Specimen Type / Requirements

Container Type = 1 Green top (LiHep) and 1 Red Top

Minimum Volume: 5mL on Red Top and 5-7 mL on green top.

Tube must fill to at least ½ or greater of its vacuum capacity

Specimen Handling

Collection Instructions: Collect 1 green top and 1 red top for enzyme screening. Write your initials, date and time of collection on the collection label or requisition.

Note: Collect 1 lavender top if test requested is Tay-Sachs Genetics Screening. This Information should be indicated in the requisition.

Special Instructions The specimen should be shipped on a Monday, to Thursday so that the Laboratory will receive the specimen within 24 hours after collection. Ship at room temperature. Blood samples at room temperature must be received within 24 hours after collection, arriving at SickKids by 1200hr (noon)

Rejection Criteria: Serum , Plasma, Frozen, Sample more than 24hrs old. Unlabeled or Not Sufficient Quantity Samples will be rejected.

Stability: Stable at room temperature for 24hrs

Transportation: Send sample to core lab as soon as possible. Ship Monday – Friday only, excluding statutory holidays. Do NOT freeze or refrigerate blood

Required Documentation

Turnaround Time (TAT)

2 weeks (Prenatal samples), 2-3 weeks (Pregnancy/Urgent samples), 4-6 weeks (Routine)

Test Utilization

Reference Value

See Report

Test Code



Targeted analysis of recurrent mutations

Testing Location

Referred Out – ON, Canada (ROSK01)

Other Information