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Comprehensive Spinocerebellar Ataxia Repeat Expansion Panel (SCA 1, 2, 3, 6, 7, 8, 10, 12, 17, 36, & DRPLA)

CPT: 81178, 81179, 81180, 81184, 81181, 81182, 81183, 81343, 81344, 81479, 81177
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Special Instructions

This assay is available for New York State.



Specimen Requirements


Specimen

Blood | Extracted DNA


Volume

Blood: Draw blood in a lavender top EDTA tube, Sample Stability: 5-7 days, Preferred volume: 4 ml, Minimum volume: 2 ml, DO NOT FREEZE. Extracted DNA: From leukocytes, muscle, or fibroblasts: Preferred quantity: 1 microgram, Minimum quantity: 800 nanograms. Genomic DNA should be eluted in sterile Dnase/Rnase free water or TE. The A260:A280 ratio should be 1.8-2.0.


Container

Blood: Lavender-Top (EDTA) Tube, Extracted DNA: Sterile screw capped vial


Collection

Blood: Specimens should be shipped overnight in a secure container at room temperature. Extracted DNA: Should be shipped overnight at room temperature. If previously frozen, DNA can be shipped in an insulated container with wet or dry ice.


Storage Instructions

Blood - ship ASAP, but stable up to 5 days post-collection at room temperature. DO NOT FREEZE; Swab - 60 day post-collection room temperature stability; DNA - ship at room temperature after extraction; Fibroblasts - ship flask in insulated container at room temp or refigerated; Muscle - ship in insulated container with 5-7 lbs of dry ice


Stability Requirements

Room Temperature: Blood - 5 days, Swab - 60 days, DNA - 30 days, Muscle - 0 days, Fibroblasts - 2-3 days; Refrigerated: Blood - 5 days, Swab - 60 days, DNA - 30 days, Muscle - 0 days, Fibroblasts - 2-3 days; Frozen: Blood - DO NOT FREEZE, Swab - 60 days, DNA - Indefinitely, Muscle - Indefinitely, Fibroblasts - Indefinitely; Freeze/Thaw: None


Causes for Rejection

Extracted DNA A260:A280 ratio of outside of 1.8-2.0 range; Frozen blood EDTA tube; Thawed and/or fatty muscle sample; Insufficient buccal cell collection


Test Details


Limitations

Maximum reportable sizing: ATN1 – 110 repeats, ATXN1 – 150 repeats, ATXN10 – 90 repeats, ATXN2 – 150 repeats, ATXN3 – 120 repeats, ATXN7 – 125 repeats, ATXN8OS/ATXN8 – 150 repeats, CACNA1A – 145 repeats, NOP56 – 65 repeats, PPP2R2B – 150 repeats, TBP – 120 repeats

SCA1 repeat expansion testing is unable to determine if an allele greater than 40 repeats contains CAT interruptions.


Methodology

Repeat-Primed PCR (QP-PCR)


Recommended MNG Kits

SINGLE Blood Genetic Testing


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