genetics
Last reviewed 01/2018
Abetalipoproteinaemia is a rare autosomal recessive disorder.
In some of the patients where a genetic defect has been determined the apolipoprotein B gene is normal; these patients have a cDNA coding for a mutant of the large subunit of microsomal triglyceride transfer protein (MTP).
MTP catalyses the transfer of triglyceride, cholesteryl ester and phospholipid between phospholipid surfaces. In the presence of an abnormal large subunit of MTP lipoproteins containing apolipoprotein B cannot be assembled. The redundant apoB is degraded intracellularly.