• 1
    Mudd SH, Levy HL, Skovby F. Disorders of transsulphation. In The Metabolic Basis of Inherited Disease, 7th edn, eds ScriverCR, BeaudetAL, SlyWS, ValleD. New York: McGraw-Hill, 1995: 12791327.
  • 2
    Fenton WA, Rosenberg LE. Inherited disorders of cobolamin transport and metabolism. In The Metabolic Basis of Inherited Disease, 7th edn, eds ScriverCR, BeaudetAL, SlyWS, ValleD. New York: McGraw-Hill, 1995: 31293149.
  • 3
    Rosenblatt DS. Inherited disorders of folate transport and metabolism. In The Metabolic Basis of Inherited Disease, 7th edn, eds ScriverCR, BeaudetAL, SlyWS, ValleD. New York: McGraw-Hill, 1995: 31113128.
  • 4
    Mudd SH, Skovby F, Levy HL, et al. The natural history of homocystinuria due to cystathionine β-synthase deficiency. Am J Hum Genet 1985; 37: 131.
  • 5
    Wilcken DEL, Wilcken B. The natural history of vascular disease in homocystinuria and the effects of treatment. J Inherit Metab Dis 1997; 20: 295300.
  • 6
    Burke JP, O'Keefe M, Bowell R, Naughten ER. A closer look in the eye in homocystinuria: a screened population. J Inherit Metab Dis 1988; 11(Suppl 2): 237239.
  • 7
    Walter JH, Wraith JE, White FJ, Bridge C, Till J. Strategies for the treatment of cystathionine β-synthase deficiency: the experience of the Willink Biochemical Genetics Unit over the past 30 years. Eur J Pediatr 1998; 157(Suppl 2): S71S76.
  • 8
    Komrower GM, Lambert AM, Cusworth DC, Westall RG. Dietary treatment of homocystinuria. Arch Dis Child 1966; 41: 666671.
  • 9
    Perry TL, Hansen S, Love DL, Crawford LE, Tischler B. Treatment of homocystinuria with a low-methionine diet, supplemental cysteine, and a methyl donor. Lancet 1968; ii: 474478.
  • 10
    Smolin LA, Benevenga NJ, Berlow S. The use of betaine for the treatment of homocystinuria. J Pediatr 1981; 99: 467472.
  • 11
    Wilcken DEL, Wilcken B, Dudman NPB, Tyrrell PA. Homocystinuria- The effects of betaine in the treatment of patients not responsive to pyridixime. N Engl J Med 1983; 309: 448453.
  • 12
    Holme E, Kjellman B, Ronge E. Betaine for the treatment of homocysteine caused by methylenetetrahydrofolate reductase deficiency. Arch Dis Child 1989; 64: 10611064.
  • 13
    Wendel U, Bremer HJ. Betaine in the treatment of homocystinuria due to 5, 10-methylenetetrahydrofolate reductase deficiency. Eur J Pediatr 1984; 142: 147150.
  • 14
    Bartholomew DW, Batshaw ML, Allen RH, et al. Therapeutic approaches to cobolamin-C methylmalonic acidaemia and homocystinuria. J Pediatr 1988; 112: 3239.
  • 15
    Berlow S, Bachmann RP, Berry GT, et al. Betaine therapy in homocystinuria. Brain Dysfunction 1989; 2: 1024.
  • 16
    Brens CM, Serra JD, Tomas MLC, Gomez AMG, Monegal MR, Busca AV. Homocistinuria. Eficacia del tratamiento con piridoxina, acido folico y betaina. An Esp Pediatr 1993; 39: 3741.
  • 17
    Kishi T, Kawamura I, Harada Y, et al. Effects of betaine on S-adenosylmethionine levels in the cerebrospinal fluid in a patient with methyltetrahydrofolate reductase deficiency and peripheral neuropathy. J Inher Metab Dis 1994; 17: 560565.
  • 18
    Gahl WA, Bernadini I, Chen S, Kurtz D, Horvath K. The effect of oral betaine on vertebral body bone density in pyridixine-non-responsive homocystinuria. J Inher Metab Dis 1988; 11: 291298.
  • 19
    Sakura N, Ono H, Nomura S, Ueda H, Fujita N. Betaine dose and treatment intervals for homocystinuria due to 5,10-methylenetetrahydrofolate reductase deficiency. J Inher Metab Dis 1998; 21: 8485.
  • 20
    Schwahn B, Hafner D, Hohlfeld T, Laryea MD, Wendle U. Pharmacokinetics of oral betaine in healthy subjects. J Inher Metab Dis 2000; 23: (Suppl 1): 66, 131-O.
  • 21
    Laryea MD, Steinhagen F, Pawliczek S, Wendle U. Simple method for the routine determination of betaine and DMG in blood and urine. Clin Chem 1998; 44: 19371941.
  • 22
    Moat SJ, Bonham JR, Tanner MS, Allen JC, Powers HJ. Recommended approaches for the laboratory measurement of homocysteine in the diagnosis and monitoring of patients with hyperhomocysteinaemia. Ann Clin Biochem 1999; 36: 372379.
  • 23
    Piotrovsky VK. Indirect pharmacodynamic response models do not require any parametric pharmacokinetic model to be fitted to effect time data. Meth Find Exp Clin Pharmacol 1997; 19: 723729.
  • 24
    Allen RH, Stabler SP, Lindenbaum J. Serum betaine, N,N-dimethylglycine and N-methylglycine levels in patients with cobalamin and folate deficiency and related errors of metabolism. Metabolism 1993; 42: 14481460.
  • 25
    Walson PD. Paediatric clinical pharmacology and therapeutics. In Avery's Drug Treatment, 4th edn, eds SpeightTM, HolfordNG. Auckland: Adis International, 1997: 127172.
  • 26
    Bonate PL. Clinical trial simulation in drug development. Pharm Res 2000; 17: 252256.