Despite Pi*S prevalence is high in southwestern European countries, there is scarce information available about the Pi*SS genotype.
Considering that the European region has a high prevalence of carriers of the Pi*S allele and seems to concentrate the largest number of individuals with the Pi*SS genotype, we believe that this EARCO study proposal is pertinent and relevant to better understand this genotype, its prevalence, natural history, and risk for disease, when compared to Pi*SZ and Pi*ZZ genotypes.