Screening for mutations by expressing patient cDNA segments in E. coli: Homocystinuria due to cystathionine β‐synthase deficiency

@article{Koich1992ScreeningFM,
  title={Screening for mutations by expressing patient cDNA segments in E. coli: Homocystinuria due to cystathionine $\beta$‐synthase deficiency},
  author={Viktor Ko{\vz}ich and Jan P Kraus},
  journal={Human Mutation},
  year={1992},
  volume={1}
}
Deficiency of cystathionine β‐synthase (CBS) causes the most common form of inherited homocystinuria. We developed a simple CBS expression system in E. coli to screen for pathogenic mutations in affected individuals. Portions of patient cDNAs were amplified by PCR and used to replace the corresponding segments of normal human CBS cDNA in the bacterial expression plasmid pHCS3. Hybrid CBS was expressed in E. coli and the segments of patient's cDNA which extinguished CBS activity were sequenced… Expand
Mutational analysis of the cystathionine β‐synthase gene: A splicing mutation, two missense mutations and an insertion in patients with homocystinuria
RT‐PCR and direct sequence analyses were used to define mutations in the cystathionine β‐synthase (CBS) gene in two unrelated male patients with vitamin B6 nonresponsive homocystinuria. Both patientsExpand
Characterisation of Five Missense Mutations in the Cystathionine Beta-Synthase Gene from Three Patients with B6-Nonresponsive Homocystinuria
TLDR
The identification of 5 missense mutations in the protein-coding region of the CBS gene from 3 patients with pyridoxine-nonresponsive homocystinuria confirmed the association between the individual mutation and CBS dysfunction in each patient. Expand
Detection of a novel deletion in the cystathionine β‐synthase (CBS) gene using an improved genomic DNA based method 1
We elucidated the intron‐exon boundaries of the 15 coding exons of the human cystathionine β‐synthase (CBS) gene in order to establish an improved method based on PCR and direct sequencing forExpand
Four novel mutations in the cystathionine β‐synthase gene: Effect of a second linked mutation on the severity of the homocystinuric phenotype
TLDR
Four novel missense mutations in the CBS gene are reported, raising the possibility that double mutant alleles may be underestimated in homocystinuric patients and a search for additional mutations in cis may sometimes be necessary to establish a good genotype‐phenotype relationship. Expand
The c.797 G>A (p.R266K) cystathionine β‐synthase mutation causes homocystinuria by affecting protein stability
TLDR
These studies show that the p.R266K mutation causes increased proteasomal degradation in vivo, and that treatments that stabilize the protein can be used to reverse its effect. Expand
Defective cystathionine beta-synthase regulation by S-adenosylmethionine in a partially pyridoxine responsive homocystinuria patient.
TLDR
The presence of a homozygous G1330A mutation in the CBS cDNA indicates the importance of S-adenosylmethionine regulation of the transsulfuration pathway in homocysteine homeostasis in humans and suggests that this D444N mutation interferes in S- adenosyl methionines regulation of CBS. Expand
Reduced response of Cystathionine Beta-Synthase (CBS) to S-Adenosylmethionine (SAM): Identification and functional analysis of CBS gene mutations in Homocystinuria patients
TLDR
A deficient regulation of CBS by SAM is experimentally supported as a frequently found mechanism in CBS deficiency, which should be considered not only as a valuable diagnostic tool but also as a potential target for the development of new therapeutic approaches in classical homocystinuria. Expand
Molecular analysis of patients affected by homocystinuria due to cystathionine β-synthase deficiency: report of a new mutation in exon 8 and a deletion in intron 11
TLDR
Two independent patients are reported showing a novel mutation in exon 8 and a 49bp deletion located in intron 11, respectively, and the occurrence of four relatively common mutations in 16 homocystinuric families of South European origin are tested. Expand
Simultaneous detection and screening of T833C and G919A mutations of the cystathionine beta-synthase gene by single-strand conformational polymorphism.
TLDR
SSCP of exon 8 allows screening of the heterozygous carrier state of these mutations in a large population, to determine the importance of heterozygosity of CBS mutations as the cause of mild hyperhomocyst(e)inemia associated with premature vascular diseases. Expand
Variable hyperhomocysteinaemia phenotype in heterozygotes for the Gly307Ser mutation in cystathionine beta-synthase.
TLDR
This is the first report of a normal methionine load test in a proven heterozygote for a CBS mutation which causes severe homocystinuria in the homozygote, and appears to be a common allele among families of Celtic origin. Expand
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