The associations of SERPINA1 Z (rs28929474) and S (rs17580) alleles with age at CFLD onset and the development of CFLD-related complications (severe liver disease with cirrhosis, portal hypertension, esophageal varices) were analyzed.
The Z mutation (E342K) of α1-antitrypsin (α1-AT), carried by 4% of Northern Europeans, predisposes to early onset of emphysema due to decreased functional α1-AT in the lung and to liver cirrhosis due to accumulation of polymers in hepatocytes.
The Z variant (Glu342Lys) of α(1)-antitrypsin (AT) polymerizes and accumulates in the hepatocyte endoplasmic reticulum (ER) predisposing to neonatal hepatitis and liver cirrhosis.
According to retrospective studies, up to 25% of those with homozygous ZZ (Glu 342 to Lys) AATD suffer from liver cirrhosis and/or liver cancer in late adulthood.