Pyridoxine Responsive and Unresponsive Homocystinuria

Treatment of Homocystinuria with Pyridoxine

Homocystinuria is the result of an inborn error in the metabolism of the essential sulphur-containing amino acid, methionine (Carson and Neill, 1962; Gerritsen, Vaughn, and Waisman, 1962). There is now good evidence (Mudd et al., 1964) to show that the basic defect in this disorder is an inactivity of hepatic cystathionine synthetase, which prevents the formation of cystathionine from homocyste...

Homocystinuria. Reduced folate levels during pyridoxine treatment.

Wilcken, B., and Turner, B. (1973). Archives of Disease in Childhood, 48, 58. Homocystinuria: reduced folate levels during pyridoxine treatment. Nine patients with homocystinuria due to cystathionine synthase deficiency were treated with pyridoxine: 6 responded biochemically and 5 of these showed marked clinical improvement. Full biochemical response was only obtained slowly in some patients. R...

Defective cystathionine beta-synthase regulation by S-adenosylmethionine in a partially pyridoxine responsive homocystinuria patient.

We determined the molecular basis of cystathionine beta-synthase (CBS) deficiency in a partially pyridoxine-responsive homocystinuria patient. Direct sequencing of the entire CBS cDNA revealed the presence of a homozygous G1330A transition. This mutation causes an amino acid change from aspartic acid to asparagine (D444N) in the regulatory domain of the protein and abolishes a TaqI restriction ...

Defective Cystathionine b -Synthase Regulation by S-Adenosylmethionine in a Partially Pyridoxine Responsive Homocystinuria Patient

We determined the molecular basis of cystathionine b -synthase (CBS) deficiency in a partially pyridoxine-responsive homocystinuria patient. Direct sequencing of the entire CBS cDNA revealed the presence of a homozygous G 1330 A transition. This mutation causes an amino acid change from aspartic acid to asparagine (D444N) in the regulatory domain of the protein and abolishes a TaqI restriction ...

Pyridoxine responsive epilepsy: expanded pyridoxine dependency?