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CBS Gene Mutation - (Cystathionine -Synthase Gene Mutation)

The cystathionine beta synthase (CBS) enzyme converts homocysteine
to cystathionine. The two most common mutations in the CBS gene are
the G919A and T833C substitutions resulting in a serine for glycine at
amino acid residue 307 and a threonine for isoleucine at amino acid 278,
respectively.

Patients with the T833C mutation can respond to pyridoxine therapy,
whereas, patients with the G919A mutation do not respond to pyridoxine
therapy. Thus, identification of these CBS mutations would help in the
diagnosis and treatment of homocysteinemia.

References:

1. Sperandeo, M.P., M. Panico, A. Pepe, et al., (1995) Molecular analysis
of patients affected by homocysteinuria due to cystathionine b-synthase
deficiency: report of a new mutation in exon 8 and a deletion in intron 11.
J. Inher. Metab. Dis. 18:211-4.

2. Hu, F.L., Z. Gu, V. Kozich, et al, Molecular basis of cystathionine
b-synthase deficiency in pyridoxine responsive and nonresponsive
homocystinuria. Hum Molec. Gen. 2:1857-60.

3. Sperandeo, M.P., M. Candito, G. Sebastio, et al., (1996) Homocysteine
response to methionine chalenge in four obligate heterozygotes for
homocysteinuria and relationship with cystathionine b-synthase
mutations. J. Inher. Metab. Dis. 19:351-6.

4. Kraus, J.P. (1994) Molecular basis of phenotype expression in
homocystinuria. J. Inher. Metab. Dis. 17:383-90.

5. Glueck, C. J., R. N. Fontaine, A. Gupta and M. Alasmi (1997)
Myocardial infarction in a 35-year-old man with homocysteinemia, high
plasminogen activator inhibitor activity, and resistance to activated
protein C. Metabolism 46:1470-2.

6. Glueck, C.J. M.J. Kupferminc, R.N. Fontaine, P. Wang, B.B. Weksler
and A. Eldor. (2001) Genetic hypofibrinolysis in complicated
pregnancies. Obstet. and Gynecol. 97:44-8.

For more information go to National Center for Biotechnology Information
(NCBI).
Most abstracts and many full length articles can be printed from this web site.