Date of this Version
Published in: Homocysteine Metabolism: From Basic Science to Clinical Medicine, ed. Ian Graham, Helga Refsum, Irwin H. Rosenberg, Per Magne Ueland, & Jill M. Shuman (Boston: Kluwer Academic Publishers, 1997).
Cystathionine β-synthase (CBS) deficiency was first demonstrated in 1964 in an eight-year-old mentally retarded girl with bilaterally dislocated optic lenses who excreted abnormally elevated amounts of homocystine in her urine. Patients with similar metabolic abnormalities and clinical findings had first been discovered 2 years earlier by Carson and her colleagues during a survey of mentally backward children in Northern Ireland. CBS deficiency has proven to be the most frequently encountered of the human genetic diseases causing homocystinuria and severe hyperhomocyst(e)inemia. Worldwide, it is detected with a frequency of about 1: 344,000 by screening programs of the newborn, but this is undoubtedly an underestimate because some individuals are being missed. This chapter will briefly focus on the major clinical manifestations and metabolic aspects of CBS deficiency.