Gene Linked to Cystic Fibrosis With Liver Disease
International two-stage study of suspected CFLD genes throws spotlight on SERPINA1 Z allele
TUESDAY, Sept. 8 (HealthDay News) -- The SERPINA1 Z allele is associated with severe liver disease with portal hypertension in patients with cystic fibrosis (CFLD), according to a study in the Sept. 9 Journal of the American Medical Association.
Jaclyn R. Bartlett, Ph.D., of the University of North Carolina in Chapel Hill, and colleagues recruited CFLD patients from 113 cystic fibrosis centers in the United States, Canada, and eight other countries. In the study's initial stage, 124 patients with CFLD and a control group of 843 cystic fibrosis patients without liver disease were genotyped for nine polymorphisms in five genes identified as possible modifiers for CFLD. In the second stage, 136 additional CFLD patients and a control group of 1,088 cystic fibrosis patients without liver disease were genotyped for the SERPINA1 Z allele and TGFB1 codon 10.
The researchers found that the initial stage of the study evidenced an association between CFLD and the SERPINA1 Z allele (odds ratio, 4.72) and the TGFB1 codon 10 CC genotype (odds ratio, 1.53). In the second stage, CFLD was associated with the SERPINA1 Z allele (odds ratio, 3.42) but not with TGFB1 codon 10. Analyzing the two studies in combination showed CFLD to be associated with SERPINA1 Z allele (odds ratio, 5.04).
"In summary, we studied two large populations of patients with cystic fibrosis with and without liver disease and portal hypertension to test genes previously studied as modifiers of liver disease. Of these candidate genes, only the SERPINA1 Z allele was significantly associated with CFLD and portal hypertension," the authors write.