Abetalipoproteinemia (ABL; OMIM 200100) is an inherited disorder resulting from mutations in the microsomal triglyceride transfer protein gene and characterized by a major lipid malabsorption leading to extremely low plasma cholesterol and triglyceride levels and fat-soluble vitamins deficiencies. We report two novel mutations (c.59del17 and c.582C>A) and the long-term follow-up of four ABL subjects treated with vitamin E. The good outcome of the early-treated patients contrasts with severe ataxia and retinopathy observed in the patient with delayed treatment. In conclusion, early diagnosis and early management are essential to prevent the manifestations following the fat-soluble vitamin deficiencies.