Laboratory Test Guide

Spinocerebellar Ataxia 2

General Information

Lab Name

Spinocerebellar Ataxia 2

Lab Code

SCA2T

Epic Name

Spinocerebellar Ataxia 2

Description

For further information about this test, see Spinocerebellar Ataxia Panel [SCAPN], which includes panels 1,2,3,6 and 7.

Synonyms

Olivopontocerebellar 2, OPCA2, SCA2, Spinocerebellar Atrophy 2

Components

Code Name
SCA2A1 ATXN2 (SCA2), allele 1
SCA2A2 ATXN2 (SCA2), allele 2
SCAITP SCA1 Interpretation
SCACOM SCA1 Comment
SCA2DI SCA2 Director

Interpretation

Method

Polymerase Chain Reaction (PCR)/Capillary Electrophoresis

Reference Range

See individual components

Ref. Range Notes

Normal Mutable Normal Intermediate Penetrance Full Penetrance
SCA 2 <32 repeats 32 repeats >32 repeats

Ordering & Collection

Specimen Type

Blood/Cultured amniocytes or chorionic villus cells/Extracted DNA from approved sample types (blood, chorionic villi, amniocyte). Direct chorionic villi, amniocyte, or amniotic fluid testing require Genetics Director approval. Please call the lab at 206-598-7021

Collection

Acceptable:

  1. Whole blood:5 mL lavender top (EDTA) tube or yellow (ACD) top tube or 2 mL microtainer lavender top tube

  2. Extracted DNA from blood, chorionic villi, and amniocytes: 500 ng (concentration >10 ng/uL)

  3. Cultured amniocytes/chorionic villi: MCC is required for testing fetal samples. See MCC OLTG.

  4. Also acceptable, but requires the Genetics Director's approval and a backup culture. Direct chorionic villi and/or TISSUE: Send 20mg of tissue in a sterile tube or RPMI culture media

    *NOTE: If a fetal sample (cultured amniocytes or chorionic villi) was received, add MCC to the order. Prenatal testing requires concomitant testing for maternal cell contamination (see Online Test Guide, MCC for ordering and specimen requirements). See Special Instructions.

Unacceptable: Heparin green top tubes, buccal swab

Forms & Requisitions

Genetics Requisition

Handling Instructions

SPS specimen handling:

  1. Whole blood sample: store in the refrigerator

  2. Cultured amniocytes/chorionic villi: store at room temperature. Call the Genetics lab upon receipt (206)598-7021.

  3. Extracted DNA: store in the refrigerator

Quantity

requested: Entire specimen
minimum: Blood: 1 mL. If volume is less than 1mL, do not cancel. Send to Genetics lab. Confluent cultured cells: One (1) T25 flask. Extracted DNA: 250 ng

Processing

For clients outside of UW, please include any relevant clinical history.

If fetal tissue (cultured amniocytes or chorionic villi) was received for prenatal testing, consultation with the laboratory is required. Please notify the Genetics lab about prenatal studies via email at geneticshelp@uw.edu or call 206-598-7021.

Performance

LIS Dept Code

Genetics (GEN)

Performing Location(s)

UW-MT Genetics

Attention: Genetics Lab
Clinical lab, Room NW220
University of Washington Medical Center
1959 NE Pacific Street
Seattle, WA 98195

Tel: 206-598–6429 M–F (7:30 AM–4:00 PM)
Fax: 206-616-4584
Lab email: cgateam@uw.edu

Tel (EXOME only): 206-543-0459

Faculty
Jillian Buchan, PhD, FACMG
Runjun Kumar, MD, PhD
Regina Kwon, MD, MPH
Christina Lockwood, PhD, DABCC, DABMGG
Abbye McEwen, MD, PhD
Colin Pritchard, MD, PhD
Vera Paulson, MD, PhD
Eric Konnick, MD, MS
He Fang, PhD

Frequency

Performed weekly. Results within 2-3 weeks.

Available STAT?

No

Billing & Coding

CPT codes

81179

LOINC

49646-3