A 73-year-old never-smoker woman with chronic bronchitis, increasing dyspnoea, and airflow limitation with a FEV, of 49% of predicted value had low serum level of alpha-1-antitrypsin (69 mg/dL, normal range 150-350). Isoelectric focusing showed an M like pattern. Direct sequencing showed, in the second exon, a particular DNA alteration localized between codon 41 and codon 51: a region of 30 base pairs (bp) was completely deleted and substituted by a 22-bp sequence. The resulting loss of 8 bp yields, in the second exon, a 70-71 stop codon. This new M like variant was denominated M Varallo from the site where it was discovered.
- Alpha 1-antitryspin deficiency
- Chronic airflow limitation
- New M variant
ASJC Scopus subject areas
- Pathology and Forensic Medicine