The prevalence of alpha-1 antitrypsin deficiency in Ireland

• Main Authors: Morris Valerie B, Dimitrov Borislav D, O'Brien Geraldine, Kelleher Dermot P, McPartlin Joseph, Floyd Olwen, O'Connor Catherine A, Carroll Tomás P, Taggart Clifford C, McElvaney Noel G
• Format: Article
• Language: English
• Published: BMC 2011-07-01
• Series: Respiratory Research
• Online Access: http://respiratory-research.com/content/12/1/91

<p>Abstract</p> <p>Background</p> <p>Alpha-1 antitrypsin deficiency (AATD) results from mutations in the SERPINA1 gene and classically presents with early-onset emphysema and liver disease. The most common mutation presenting with clinical evidence is the Z mutation, while the S mutation is associated with a milder plasma deficiency. AATD is an under-diagnosed condition and the World Health Organisation recommends targeted detection programmes for AATD in patients with chronic obstructive pulmonary disease (COPD), non-responsive asthma, cryptogenic liver disease and first degree relatives of known AATD patients.</p> <p>Methods</p> <p>We present data from the first 3,000 individuals screened following ATS/ERS guidelines as part of the Irish National Targeted Detection Programme (INTDP). We also investigated a DNA collection of 1,100 individuals randomly sampled from the general population. Serum and DNA was collected from both groups and mutations in the SERPINA1 gene detected by phenotyping or genotyping.</p> <p>Results</p> <p>The Irish National Targeted Detection Programme identified 42 ZZ, 44 SZ, 14 SS, 430 MZ, 263 MS, 20 IX and 2 rare mutations. Analysis of 1,100 randomly selected individuals identified 113 MS, 46 MZ, 2 SS and 2 SZ genotypes.</p> <p>Conclusion</p> <p>Our findings demonstrate that AATD in Ireland is more prevalent than previously estimated with Z and S allele frequencies among the highest in the world. Furthermore, our targeted detection programme enriched the population of those carrying the Z but not the S allele, suggesting the Z allele is more important in the pathogenesis of those conditions targeted by the detection programme.</p>