Update on Primary Hypobetalipoproteinemia
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“Primary hypobetalipoproteinemia” refers to an eclectic group of inherited lipoprotein disorders characterized by low concentrations of or absence of low-density lipoprotein cholesterol and apolipoprotein B in plasma. Abetalipoproteinemia and homozygous familial hypobetalipoproteinemia, although caused by mutations in different genes, are clinically indistinguishable. A framework for the clinical follow-up and management of these two disorders has been proposed recently, focusing on monitoring of growth in children and preventing complications by providing specialized dietary advice and fat-soluble vitamin therapeutic regimens. Other recent publications on familial combined hypolipidemia suggest that although a reduction of angiopoietin-like 3 activity may improve insulin sensitivity, complete deficiency also reduces serum cholesterol efflux capacity and increases the risk of early vascular atherosclerotic changes, despite low low-density lipoprotein cholesterol levels. Specialist laboratories offer exon-by-exon sequence analysis for the molecular diagnosis of primary hypobetalipoproteinemia. In the future, massively parallel sequencing of panels of genes involved in dyslipidemia may play a greater role in the diagnosis of these conditions.
KeywordsAbetalipoproteinemia Apolipoprotein B Chylomicron retention disease Combined hypolipidemia Familial hypobetalipoproteinemia Hypobetalipoproteinemia Low-density lipoprotein
This work was supported by National Health and Medical Research Council Project Grant 1010133 (to Amanda J. Hooper and John R. Burnett) and a Practitioner Fellowship from the Royal Perth Hospital Medical Research Foundation (to John R. Burnett).
Conflict of Interest
Amanda J. Hooper and John R. Burnett declare that they have no conflict of interest.
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