Advanced Diagnostic Laboratories

Alpha-1-Antitrypsin Levels, Genotype, and Phenotype

Test Code

A1LGP

Description

Levels: Alpha-1-Antitrypsin may be decreased in emphysema, hepatic cirrhosis, respiratory distress syndrome of the newborn, nephrosis, malnutrition and cachexia. If a deficiency is present, genotyping may be considered to confirm heterozygous versus homozygous deficiencies.

Genotype: PCR-MALDI TOF Mass spectrometry for identification of alpha-1 antitrypsin variants.
Our genotyping test identifies the presence of 20 single nucleotide polymorphisms (SNPs) in the human SERPINA1 gene, including 19 mutations and the major normal allele (M).

Phenotype: May be sent out if warranted.

Collect

Genotype: Full ACD solution A or ACD solution B vacutainer, or 2 mL whole blood aliquot from ACD-anticoagulant tube, at least 1 mL of aliquot frozen whole blood is required for testing. A full EDTA or full heparin vacutainer is also acceptable for testing. OR One buccal swab (Cat. No. Puritan 25-1506 1PF) collection is required, yet 2 buccal swabs are recommended to accommodate potential repeat testing. OR DNA extracted from any of the above specimens is acceptable if DNA yield is greater than 1 ng/mcL. The extracted DNA must come from a CLIA validated laboratory.

Levels: Collect in a plain red top or SST tube.

Phenotype: Collect in a plain red top or SST tube.

Patient Prep

Genotype:
Buccal Swab Collection: Swabs should be collected at least 20 minutes after eating by firmly scraping the swab 20 times against the inside of the subject's cheek with a rolling action.

Levels:
Onsite [NJH]: Transport to lab within 1 hour.
Offsite: Separate serum from cells within 2 hours by centrifuge and aliquot into a labeled polypropylene or similar plastic tube.
Preferred volume: 1 mL serum

Phenotype:
Send Out. Separate serum from cells within 2 hours by centrifuge and aliquot into a labeled polypropylene or similar plastic tube.
Preferred volume: 1 mL serum

Pediatric Collection

Levels - Minimum Volume: 0.5 mL serum
Genotype - Minimum volume: 1 mL whole blood
Phenotype - Minimum Volume:0.5 mL serum

Unacceptable Conditions

Genotype: Sample received outside stability or at an incorrect temperature.

Levels: Gross Lipemia

Phenotype: Plasma, lipemic, grossly hemolyzed, microbially contaminated specimens, or specimens with visible particulates should not be used.

Storage Transport Temp

Genotype: Samples may be shipped overnight at ambient temperature, refrigerated or frozen on dry ice.

Levels: Send frozen serum Priority Overnight via FedEx and in a well-insulated container on dry ice.

Phenotype: Send frozen serum Priority Overnight via FedEx and in a well-insulated container on dry ice.

Stability

Genotype:
Whole blood: No longer than 1 week at room temperature or no longer than 1 month at 2-8°C. Long-term storage must be at or below -20 °C in a 24-hour monitored freezer. Buccal swabs: Room temperature for up to 3 months or less than or equal to 8°C indefinitely. DNA samples: Store no longer than 1 month at 2-8°C and long-term at or below -20oC in a 24-hour monitored freezer.

Levels:
Stability after cell separation:
8 hours at room temperature (15-25°C)
24 hours refrigerated at 2-8°C
>24 hours frozen at -20°C

Phenotype:
Stability after cell separation:
8 hours at room temperature (15-25°C)
24 hours refrigerated at 2-8°C
>24 hours frozen at -20°C

Performed

Genotype: Bi-weekly

Levels: Monday - Friday

Methodology

Genotype: PCR-MALDI TOF Mass spectrometry for identification of alpha-1- antitrypsin variants from nucleic acid.

Levels: Turbidimetric

Phenotype: Electrophoresis and Nephelometry

Turnaround Time

10-14 business days

Phenotype: Send out

Department

Immunology Lab - Diagnostic

Synonyms

AAT

Study Offerings

CAP/CLIA

Related Tests

AATPG, A1AT, A1ATG

Reference Interval

Genotype: M/M

Phenotype: M

Level:

AGE	MALE / FEMALE (mg/dL)
Newborn - 30 days	124 - 348
31 days - 5 months	111 - 297
6 months - 1 year	95 - 251
2 - 19	110 - 279
20+	72 - 192

Interpretation

Genotype: Interpretation will reflect on the Final Report.

This genetic assay will detect the normal M allele and the following 19 mutations: S, Z, F, I, Q0casablanca, Pittsburgh, Mheerlen, Mmalton, Mmineral springs, Mprocida, Plowell, Q0clayton, Q0newport, Q0bellingham, Q0granite falls, Q0ludwigshafen, Q0mattawa, Q0west, Siiyama. This assay does not rule out the existence of very rare mutations when an "M" result is reported.