Novel APOB nonsense variant related to familial hypobetalipoproteinemia and hepatic steatosis: A case report and review.

• Familial hypobetalipoproteinemia is caused by monoallelic variants in APOB. • Metabolic Associated Fatty Liver Disease is the main associated comorbidity. • We report a novel APOB nonsense variant and present a short review about this entity. • We propose a support algorithm for the clinical diagnosis of this syndrome. Hereditary familial hypobetalipoproteinemia (FHBL) is a syndrome caused by variants in the APOB gene, that cause a defect in the secretion and mobilization of liver lipids to peripheral tissues, associated with the synthesis of truncated ApoB100 apolipoproteins. This condition causes significant reduction in total cholesterol (TC), low-density lipoproteins (LDL), very low-density proteins (VLDL) and serum triglyceride levels, with unchanged high-density lipoprotein (HDL) cholesterol levels. Herein we present the case of a middle-aged woman diagnosed with FHBL and hepatic steatosis, heterozygous for c.4698C>A; (p.Tyr1566Ter) variant in APOB. The variant presented herein showed high expressiveness in the two generations of individuals analyzed and has not yet being described in the medical literature. Early diagnosis and screening for associated metabolic comorbidities such as metabolic fatty liver disease and its subsequent progression to fibrosis are the two main goals in the treatment of this condition, in order to prevent medium to long term potential complications. [ABSTRACT FROM AUTHOR]