HLA PHENOTYPES AND GENE POLYMORPHISMS IN JUVENILE LIVER-DISEASE ASSOCIATED WITH ALPHA-1-ANTITRYPSIN DEFICIENCY

Chronic liver disease affects up to 20% of children with α‐antitrypsin deficiency owing to the PiZZ genotype. Previous observations of a familial occurrence and abnormal immune responses to liver antigens in these patients suggests that immunoregulatory genes may be involved in the pathogenesis of liver damage. We have identified HLA phenotypes and class II (HLA‐DR) gene polymorphisms in 140 white PiZZ subjects, of whom 92 (83 index patients) had liver disease, and 206 first‐degree relatives. DR3* was present in 35 of 75 (46.7%) unrelated patients with liver disease compared with 5 of 28 (17.8%) patients without (p < 0.01) and 23 of 100 controls (p < 0.001). DR4 was increased in patients without liver disease; it was present in 17 of 28 (60.7%) compared with 29 of 75 (38.7%) patients with liver disease (p < 0.05) and 36 of 100 controls (p < 0.025). Using Southern blot analysis with HLA‐DRB and DQB DNA probes, we identified two polymorphisms of DR3, only one (Dw25) of which is raised in PiZZ individuals with liver disease (9 of 55: 16.4%) compared with 1 of 23 (4.4%) without and 2 of 52 (3.9%) controls (p < 0.05). Analysis of the segregation of HLA haplotypes in 77 families revealed no concordance for liver disease with HLA in those with affected sibships, indicating that, although DR3‐Dw25 is associated with liver disease in α1‐antitrypsin deficiency, other factors must play a pathogenic role. (HEPATOLOGY 1990;12:218–223). Copyright © 1990 American Association for the Study of Liver Diseases