Challenges in understanding the consequences of variants in ABCB4 gene.

Keywords: ABCB4; MDR3; Genetic cholestasis EN ABCB4 MDR3 Genetic cholestasis 242 243 2 11/26/20 20210101 NES 210101 To the Editor: We read with interest the review by Stattermayer et al.[1] which provides a summary of ABCB4 variants in liver disease and the spectrum of clinical manifestations. We agree that compound-heterozygotes and homozygotes for ABCB4 variants have higher rates of cirrhosis, whilst heterozygotes generally have less severe liver disease. This therefore represents a rare example of how a homozygote for a protein-truncating variant can manifest a milder phenotype of ABCB4-associated liver disease. [Extracted from the article]