Cystathionine beta-synthase deficiency: effects of betaine supplementation after methionine restriction in B6-nonresponsive homocystinuria

Genet Med. 2004 Mar-Apr;6(2):90-5. doi: 10.1097/01.gim.0000117334.84388.f4.

Abstract

Purpose: For treatment of cystathionine beta-synthase (CbetaS) deficiency, we determined the effect of betaine (N,N,N-trimethylglycine) therapy and examined the genotype-phenotype relationships to betaine.

Methods: In five patients with B6-nonresponsive homocystinuria, we defined the CbetaS genotypes and determined metabolic responses to betaine as an additive to traditional dietary methionine restriction.

Results: After betaine therapy, tHcy declined (mean 47.4 micromol/L; range: -21.2 to -104.0 micromol/L; P=0.02), whereas total plasma cysteine and methionine did not change. Plasma methionine/tHcy ratios increased by 5.45 (range: +1.5 to 15.3; P=0.05) inpatients with B6-nonresponsive alleles.

Conclusion: Betaine improves metabolic control in B6-nonresponsive patients with homocystinuria after optimum dietary control.

Publication types

  • Comparative Study
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adolescent
  • Adult
  • Betaine / metabolism
  • Betaine / therapeutic use*
  • Child
  • Chromatography, High Pressure Liquid
  • Chromatography, Ion Exchange
  • Cystathionine beta-Synthase / genetics
  • Cysteine / blood
  • DNA Primers
  • Dietary Supplements
  • Genotype
  • Homocysteine / blood*
  • Homocysteine / metabolism
  • Homocystinuria / drug therapy*
  • Homocystinuria / genetics
  • Humans
  • Infant
  • Methionine / blood
  • Sequence Analysis, DNA

Substances

  • DNA Primers
  • Homocysteine
  • Betaine
  • Methionine
  • Cystathionine beta-Synthase
  • Cysteine