SERPINA1 gene variants in individuals from the general population with reduced alpha1-antitrypsin concentrations

BACKGROUND: Individuals with severe deficiency in serum alpha(1)-antitrypsin (AAT) concentrations are at high risk for developing chronic obstructive pulmonary disease (COPD), whereas those carrying the PI*MZ genotype are at slightly increased risk. Testing appropriate subgroups of the population for AAT deficiency (AATD) is therefore an important aspect of COPD prevention and timely treatment. We decided to perform an exhaustive investigation of SERPINA1 gene variants in individuals from the general population with a moderately reduced serum AAT concentration, because such information is currently unavailable. METHODS: We determined the Z and S alleles of 1399 individuals enrolled in the Swiss Cohort Study on Air Pollution and Lung Diseases in Adults (SAPALDIA) with serum AAT concentrations 5 sequencing. RESULTS: We found that 900 of 1399 samples (64%), carried the normal PI*MM genotype, whereas 499 samples (36%) carried at least 1 SERPINA1 deficiency variant. In the subpopulations in which AAT concentrations ranged from > 1.03 to 0.93 to 0.73 to < or = 0.83 g/L. CONCLUSIONS: This analysis provided a detailed molecular definition of intermediate AATD, which would be helpful in the diagnostic setting