Abetalipoproteinemia is a very rare inherited disorder that affects fat metabolism, resulting in malabsorption of dietary fats, cholesterol, and fat-soluble vitamins (A, D, E and K) necessary for normal growth and development. The signs and symptoms start to appear in the first few months of life and can include developmental delay, muscle weakness and failure to thrive. Additional symptoms may develop later. Treatment involves dietary management including nutritional supplementation. The prognosis varies based on each individual case.

The disorder is known to affect about 100 people worldwide and is also referred to as Bassen-Kornzweig Syndrome. Both parents must carry the gene in order for a child to be affected.

The above information was compiled from sources including Medline and the National Institutes of Health website and the National Organization for Rare Disorders, which provides links to additional resources.