A1ALC [A Test in Focus]

David Murray, M.D., Ph.D., provides a brief overview of the new Alpha-1-Antitrypsin Proteotype S/Z by LC-MS/MS, Serum test now available from Mayo Medical Laboratories. This test should be ordered for individuals suspected of A1A deficiency and can be used for diagnosis and identification of a specific proteotype to determine prognosis.

  • Determining the specific proteotype for prognosis and genetic counseling for patients with alpha-1-antitrypsin deficiency
  • Alpha-1-antitrypsin (A1A) inhibits the enzyme neutrophil elastase. This function is especially important in the lungs because it protects against excess tissue degradation.
  • Patients with AIA deficiency may be misdiagnosed as having asthma because the symptoms (cough, wheezing, and dyspnea with exertion) are similar.
  • A1A deficiency is a relatively common disorder in Northern European Caucasians.
  • A1A is produced by the liver and mutations in the protein can cause defective transport out of the liver resulting in liver cell destruction and elevated liver enzymes.
  • The combination of quantitation of the serum A1A and A1A proteotype determination by mass spectrometry is Mayo Clinic’s preferred approach to diagnose A1A deficiency.
  • When the serum level differs from what is expected for that proteotype, additional studies are performed that may include A1A phenotyping by isoelectric focusing and DNA sequencing.

When should I order this test?

This test should be ordered for individuals suspected of A1A deficiency. The test can be used for diagnosis and to identify a specific proteotype to determine prognosis.

  • A1ALC: Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)
  • AATP: Nephelometry


  • Day(s) and Time(s) Test Performed: Monday and Thursday; 12:00 p.m.
  • Test reported Tuesday and Friday; 11:00 a.m.
  • Analytic Time: 4 days

Andy Tofilon

Andy Tofilon is a Marketing Segment Manager at Mayo Medical Laboratories. He leads strategies for corporate communications, public relations, and new media innovations. Andy has worked at Mayo Clinic since 2003. Outside of work, Andy can be found running, hiking, snapping photos, and most importantly, spending time with his family.