Genetic diagnosis of α1-antitrypsin deficiency using DNA from buccal swab and serum samples.

BACKGROUND

α1-Antitrypsin deficiency (AATD) is associated with a high risk of developing lung and liver disease. Despite being one of the most common hereditary disorders worldwide, AATD remains under-diagnosed and prolonged delays in diagnosis are usual. The aim of this study was to validate the use of buccal swab samples and serum circulating DNA for the complete laboratory study of AATD.

METHODS

Sixteen buccal swab samples from previously characterized AATD patients were analyzed using an allele-specific genotyping assay and sequencing method. In addition, 19 patients were characterized by quantification, phenotyping and genotyping using only serum samples.

RESULTS

The 16 buccal swab samples were correctly characterized by genotyping. Definitive results were obtained in the 19 serum samples analyzed by quantification, phenotyping and genotyping, thereby performing the complete AATD diagnostic algorithm.

CONCLUSIONS

Buccal swab samples may be useful to expand AATD screening programs and family studies. Genotyping using DNA from serum samples permits the application of the complete diagnostic algorithm without delay. These two methods will be useful for obtaining more in depth knowledge of the real prevalence of patients with AATD.