Characterization of a mutant form of human apolipoprotein B (Thr26_Tyr27del) associated with familial hypobetalipoproteinemia.

We have previously identified a deletion mutant of human apoB [apoB (Thr26_Tyr27del)] in a subject with primary hypobetalipoproteinemia. The present study determined the effect of Thr26_Tyr27del mutation on apoB secretion using transfected McA-RH7777 cells. Transient or stable transfection of apoB-48 containing the Thr26_Tyr27del mutation showed drastically reduced secretion of the mutant as compared to wild-type apoB-48.

Homozygous familial hypobetalipoproteinemia: A Turkish case carrying a missense mutation in apolipoprotein B.

The autosomal co-dominant disorder familial hypobetalipoproteinemia (FHBL) may be due to mutations in the APOB gene encoding apolipoprotein B (apoB), the main constituent peptide of chylomicrons, very low and low density lipoproteins. We describe an 11month-old child with failure to thrive, intestinal lipid malabsorption, hepatic steatosis and severe hypobetalipoproteinemia, suggesting the diagnosis of homozygous FHBL, abetalipoproteinemia (ABL) or chylomicron retention disease (CMRD). The analysis of candidate genes showed that patient was homozygous for a variant (c.

The Janus-faced manifestations of homozygous familial hypobetalipoproteinemia due to apolipoprotein B truncations.

Familial hypobetalipoproteinemia is a codominant disorder characterized by low plasma levels of low-density lipoprotein cholesterol and apolipoprotein B (apoB), which in ∼50% of the cases is due to mutations in APOB gene. In most cases, these mutations cause the formation of truncated apoBs of various sizes, which have a reduced capacity to bind lipids and form lipoprotein particles. Here, we describe 2 children with severe hypobetalipoproteinemia found to be homozygous for novel APOB gene mutations.

Familial hypobetalipoproteinemia: analysis of three Spanish cases with two new mutations in the APOB gene.

Extremely low LDL-cholesterol concentrations are very unusual and generally related with comorbidities accompanying malnutrition. Less frequently low LDL-cholesterol levels result from mutations in the APOB, PCSK9, ANGPTL3, SAR1B and MTTP genes (primary hypobetalipoproteinemia). We investigated three patients with plasma LDL-cholesterol levels below the fifth percentile of the Spanish population.