Aim: Severe alpha(1)-antitrypsin (AAT) deficiency is one of the most common genetic disorders in Caucasians. The aim of the present study was to assess an unbiased frequencies of PI*S and PI*Z alleles using genotyping of a representative sample from the general population of Poland.
Methods: A random sample of age- and gender-stratified residents, aged 20 years or older, was drawn from the municipal directory of Kraków, Poland. The two most common deficiency alleles: PI*S and PI*Z were genotyped with qualitative real-time PCR using degenerative dual-labeled allele-specific fluorescent probes.
Results: In the total population of 859 adult subjects (mean age: 49.5 years; range: 20-90), 28 heterozygotes MS, 18 heterozygotes MZ and one homozygote S were diagnosed. The frequency of PI*S allele was 17.5 (95% CI: 11.6-23.9) per 1000; and that of PI*Z was 10.5 (95% CI: 5.8-15.7) per 1000. Therefore, the estimated prevalence of inherited severe AAT deficiency (homozygotes Z) in Poland is 1/9110 (95% CI: 1/4057-1/29,727).
Conclusions: In the whole population of Poland comprising 38 millions, one may expect of about 4189 (95% CI: 1284-9406) subjects with severe AAT deficiency. These numbers are high enough to consider genetic testing being introduced into a common clinical practice.