Abetalipoproteinemia is an autosomal recessive disease caused by pathogenic variants in the MTTP gene and has the highest prevalence in the Ashkenazi Jewish population. Abetalipoproteinemia results from impaired absorption of dietary fats, cholesterol and fat-soluble vitamins. Clinically, this disease can cause failure to thrive, diarrhea, fatty stools, and abnormally shaped red blood cells. The resulting vitamin deficiency can also cause ataxia and retinitis pigmentosa in adulthood. Without treatments, life expectancy is significantly reduced, but with medical management patients may have a near-normal lifespan. No genotype-phenotype correlation has been reported.
For information about carrier frequency and residual risk, please see the residual risk table.