Postprandial lipid absorption in seven heterozygous carriers of deleterious variants of MTTP in two abetalipoproteinemic families

•Genetic, clinical, ultrastructural, and biological characteristics of a new abetalipoproteinemia (ABL) case. •Postprandial studies in the new ABL case and 7 heterozygous carriers. •Normal lipid absorption in MTTP heterozygotes except if additional APOB alteration. •Need for genetic cascade screening in ABL relatives. •Need for liver and lipid absorption monitoring in ABL heterozygotes. Background Abetalipoproteinemia, a recessive disease...