Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
13
pubmed:dateCreated
1998-3-18
pubmed:abstractText
Cystathionine beta-synthase (CBS) deficiency is an autosomal recessive disorder which results in extremely elevated levels of total plasma homocysteine (tHcy) and high risk of thromboembolic events. About half of all patients diagnosed with CBS deficiency respond to pyridoxine treatment with a significant lowering of tHcy levels. We examined 12 CBS-deficient patients from 10 Norwegian families for mutations in the CBS gene and identified mutations in 18 of the 20 CBS alleles. Five of the seven patients classified as pyridoxine-responsive contain the newly identified point mutation, G797A (R266K). This point mutation is tightly linked with a previously identified 'benign' 68 bp duplication of the intron 7-exon 8 boundary within the CBS gene. We tested the effect of all of the mutations identified on human CBS function utilizing a yeast system. Five of the six mutations had a distinguishable phenotype in yeast, indicating that they were in fact pathogenic. Interestingly, the G797A allele had no phenotype when the yeast were grown in high concentrations of pyridoxine, but a severe phenotype when grown in low concentrations, thus mirroring the behavior in humans. These studies show that the G797A mutation is an important cause of pyridoxine-responsive CBS deficiency and demonstrate the utility of yeast functional assays in the analysis of human mutations.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0964-6906
pubmed:author
pubmed:issnType
Print
pubmed:volume
6
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2213-21
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:9361025-Adolescent, pubmed-meshheading:9361025-Adult, pubmed-meshheading:9361025-Alleles, pubmed-meshheading:9361025-Child, pubmed-meshheading:9361025-Cloning, Molecular, pubmed-meshheading:9361025-Cystathionine beta-Synthase, pubmed-meshheading:9361025-DNA Mutational Analysis, pubmed-meshheading:9361025-Exons, pubmed-meshheading:9361025-Female, pubmed-meshheading:9361025-Genes, Recessive, pubmed-meshheading:9361025-Genotype, pubmed-meshheading:9361025-Homocystinuria, pubmed-meshheading:9361025-Humans, pubmed-meshheading:9361025-Introns, pubmed-meshheading:9361025-Linkage Disequilibrium, pubmed-meshheading:9361025-Male, pubmed-meshheading:9361025-Multigene Family, pubmed-meshheading:9361025-Norway, pubmed-meshheading:9361025-Point Mutation, pubmed-meshheading:9361025-Polymorphism, Genetic, pubmed-meshheading:9361025-Polymorphism, Single-Stranded Conformational, pubmed-meshheading:9361025-Pyridoxine, pubmed-meshheading:9361025-Recombinant Fusion Proteins, pubmed-meshheading:9361025-Saccharomyces cerevisiae
pubmed:year
1997
pubmed:articleTitle
Functional modeling of vitamin responsiveness in yeast: a common pyridoxine-responsive cystathionine beta-synthase mutation in homocystinuria.
pubmed:affiliation
Division of Population Science, Fox Chase Cancer Center, Philadelphia, PA 19111, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't