scholarly journals Antisense suppression of donor splice site mutations in the dystrophin gene transcript

2013 ◽  
Vol 1 (3) ◽  
pp. 162-173 ◽  
Author(s):  
Sue Fletcher ◽  
Penny L. Meloni ◽  
Russell D. Johnsen ◽  
Brenda L. Wong ◽  
Francesco Muntoni ◽  
...  
Keyword(s):  
Splice Site ◽  
Dystrophin Gene ◽  
Donor Splice Site ◽  
Gene Transcript ◽  
Antisense Suppression ◽  
Donor Splice

scholarly journals Congenital Secondary Hypothyroidism Caused by Exon Skipping due to a Homozygous Donor Splice Site Mutation in the TSHβ-Subunit Gene

2002 ◽  
Vol 87 (1) ◽  
pp. 336-339 ◽  
Author(s):  
Joachim Pohlenz ◽  
Alexandra Dumitrescu ◽  
Ulrich Aumann ◽  
Gerhard Koch ◽  
Ralph Melchior ◽  
...  
Keyword(s):  
Splice Site ◽  
White Blood Cells ◽  
Donor Splice Site ◽  
Gene Transcript ◽  
Subunit Gene ◽  
Site Mutation ◽  
Exon 2 ◽  
Donor Splice ◽  
Secondary Hypothyroidism ◽  
Tsh Deficiency

Isolated TSH deficiency as a cause for congenital hypothyroidism is relatively uncommon. Even more rare is the identification of mutations in the TSHβ gene, only four of which have been identified. We here report a 4-month-old girl with isolated TSH deficiency born to consanguineous parents. Sequencing of the TSHβ-subunit gene revealed a homozygous G to A transition at position +5 of the donor splice site of intron 2. TSHβ gene transcript could not be obtained from fibroblasts or white blood cells by illegitimate amplification. Thus, to investigate further the mechanism leading to TSH deficiency in this patient, we used an in vitro exon-trapping system. The mutation at position +5 of the donor splicing site produced a skip of exon 2. The putative product of translation from a downstream start site is expected to yield a severely truncated peptide of 25 amino acids. Surprisingly, a missense substitution affecting the 14th amino acid of the signal peptide (SigP A14T) was found in one allele of the mother and brother. SigP 14T is polymorphic with a frequency of 1.8% and has no functional consequence.

Severe Homozygous Protein C Deficiency: Identification of a Splice Site Missense Mutation (184, Q → H) in Exon 7 of the Protein C Gene

1994 ◽  
Vol 72 (01) ◽  
pp. 065-069 ◽  
Author(s):  
J M Soria ◽  
D Brito ◽  
J Barceló ◽  
J Fontcuberta ◽  
L Botero ◽  
...  
Keyword(s):  
Missense Mutation ◽  
Gene Product ◽  
Splice Site ◽  
Protein C ◽  
Purpura Fulminans ◽  
Single Strand Conformation Polymorphism ◽  
Donor Splice Site ◽  
Protein C Deficiency ◽  
Donor Splice ◽  
Newborn Child

SummarySingle strand conformation polymorphism (SSCP) analysis of exon 7 of the protein C gene has identified a novel splice site missense mutation (184, Q → H), in a newborn child with purpura fulminans and undetectable protein C levels. The mutation, seen in the homozygous state in the child and in the heterozygous state in her mother, was characterized and found to be a G to C nucleotide substitution at the -1 position of the donor splice site of intron 7 of the protein C gene, which changes histidine 184 for glutamine (184, Q → H). According to analysis of the normal and mutated sequences, this mutation should also abolish the function of the donor splice site of intron 7 of the protein C gene. Since such a mutation is compatible with the absence of gene product in plasma and since DNA sequencing of all protein C gene exons in this patient did not reveal any other mutation, we postulate that mutation 184, Q → H results in the absence of protein C gene product in plasma, which could be the cause of the severe phenotype observed in this patient.

Construction of a helper cell line for avian reticuloendotheliosis virus cloning vectors

1983 ◽  
Vol 3 (12) ◽  
pp. 2241-2249
Author(s):  
S Watanabe ◽  
H M Temin
Keyword(s):  
Cell Line ◽  
Thymidine Kinase ◽  
Splice Site ◽  
Virus Production ◽  
Helper Virus ◽  
Donor Splice Site ◽  
Reticuloendotheliosis Virus ◽  
Donor Splice ◽  
Proviral Dna ◽  
Viral Dnas

We wished to construct cell lines that supply the gene products of gag, pol, and env for the growth of replication-defective reticuloendotheliosis retrovirus vectors without production of the helper virus. To do this, first we located by S1 mapping the donor and acceptor splice sites of reticuloendotheliosis virus strain A. The donor splice site is ca. 850 base pairs from the 5' end of proviral DNA. It is close to or overlaps the encapsidation sequences for viral RNA. The splice acceptor site is ca. 5.6 kilobase pairs from the 5' end of proviral DNA. Therefore, the encapsidation sequences and the donor splice site were removed from viral DNA to give expression of the gag and pol genes without virus production. The promoter in the long terminal repeat was fused to a site near the first ATG codon of the env gene, thereby deleting the encapsidation sequences and the gag and pol genes to give expression of the env gene without virus production. The permissive canine cell line D17 was transfected with the two modified viral DNAs. Two cell clones that contain both modified viral DNAs support the production of replication-defective spleen necrosis virus-thymidine kinase recombinant retrovirus vectors without the production of helper virus. To prevent recombination, the vector contains deletions that overlap with deletions in the integrated helper virus DNAs. This helper cell-vector system will be useful to derive infectious recombinant virus stocks of high titer (over 10(5) thymidine kinase transforming units per ml) which are able to infect avian, rat, and dog cells without the aid of helper virus.

Molecular Mechanisms of FVII Deficiency: Expression of Mutations Clustered in the IVS7 Donor Splice Site of Factor VII Gene

Blood ◽  
1998 ◽  
Vol 92 (5) ◽  
pp. 1646-1651 ◽  
Author(s):  
M. Pinotti ◽  
R. Toso ◽  
R. Redaelli ◽  
M. Berrettini ◽  
G. Marchetti ◽  
...  
Keyword(s):  
Splice Site ◽  
Molecular Mechanisms ◽  
Catalytic Domain ◽  
Point Mutations ◽  
Factor Vii ◽  
Donor Splice Site ◽  
Donor Splice ◽  
Expression Studies ◽  
Fvii Deficiency ◽  
American Society

Abstract In three Italian patients, two point mutations and a short deletion were found in the intron 7 of factor VII gene, clustered in the donor splice site and located in the first of several repeats. The mutation 9726+5G→A, the most frequent cause of symptomatic factor VII deficiency in Italy, as well as the deletion (9729del4) gave rise in expression studies to abnormally spliced transcripts, which were exclusively produced from the cryptic site in the second repeat. The insertion in the mature mRNA of the first intronic repeat caused (9726+5G→A) a reading frameshift, abolishing most of the factor VII catalytic domain, or produced (9729del4), an altered factor with 11 additional residues, the activity of which was not detectable in the cell medium after mutagenesis and expression studies. Studies of factor VII ectopic mRNA from leukocytes and expression studies indicated that the deleted gene produced 30% of normally spliced transcript. Differently, the 9726+5G→A mutation permitted a very low level (0.2% to 1%) of correct splicing to occur, which could be of great importance to prevent the onset, in the homozygous patients, of most of the life-threatening bleeding symptoms. The 9726+7A→G mutation was found to be a rare and functionally silent polymorphism. These findings, which provide further evidence of the interplay of sequence and position in the 5′ splice site selection, throw light on the heterogeneous molecular bases and clinical phenotypes of FVII deficiency. © 1998 by The American Society of Hematology.

A Further case of β-Thalassemia with an Homozygous T→C Substitution at the Donor Splice Site of the First Intervening Sequence of the β-Globin Gene

Hemoglobin ◽  
1989 ◽  
Vol 13 (6) ◽  
pp. 619-621 ◽  
Author(s):  
A. M. Lossi ◽  
M. Milland ◽  
J. L. Bergé-Lefranc ◽  
D. Lena-Russo ◽  
H. Perrimond
Keyword(s):  
Splice Site ◽  
Globin Gene ◽  
Donor Splice Site ◽  
Donor Splice

A mutation (IVS8+0.6kbdelTC) creating a new donor splice site activates a cryptic exon in an

1998 ◽  
Vol 103 (6) ◽  
pp. 686 ◽  
Author(s):  
R. Vervoort ◽  
Richard Gitzelmann ◽  
W. Lissens ◽  
Inge Liebaers
Keyword(s):  
Splice Site ◽  
Donor Splice Site ◽  
Cryptic Exon ◽  
Donor Splice

Characterization of a Novel Aberrant Splice Site, 79bp Downstream of Exon 5 in the Human Factor 7 Gene Detected in Patients with Severe Congenital Factor VII Deficiency.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 3481-3481
Author(s):  
Karin Wulff ◽  
Jan Astermark ◽  
Falko F H Herrmann ◽  
Günther Auerswald ◽  
Winnie Schröder
Keyword(s):  
Splice Site ◽  
Donor Splice Site ◽  
Aberrant Splice ◽  
The Novel ◽  
Splice Sites ◽  
Wild Type ◽  
Rt Pcr ◽  
Donor Splice ◽  
Naturally Occurring ◽  
Fvii Deficiency

Abstract Abstract 3481 Poster Board III-418 Hereditary FVII deficiency (FVIID) is a rare congenital bleeding disorder with an estimated prevalence of symptomatic individuals of 1:500,000. In the “Greifswald Registry FVII Deficiency” molecular defects of more than 1000 FVII deficient patients were described. By direct sequencing of the F7 genes in congenital FVIID revealed 146 different F7 gene mutations including 25 different mutations (18% of all) in the naturally-occurring acceptor or donor splice sites (Tab.1) were identified. In seven FVIID patients from Sweden and Germany the novel lesion g.IVS5+78G>A - downstream of the naturally-occurring donor splice sites of exon 5 - was identified. This variation was detected heterozygous in FVIID patients with FVII: C levels of 15%, 27%, 31%, 40% and 65%, and FVII: Ag levels between 25-50%. In two compound heterozygous patients with FVII: C levels of 1% und FVII: Ag levels of 2% and 3% respectively, one well-known causative FVII mutation is combined with the novel lesion g.IVS5+78G>A. The influence of this novel F7 gene variation on splicing was investigated by RT-PCR analysis and in vitro expression studies using exon-trap vector constructs. The total RNA was isolated from peripheral leucocytes and analyzed by one step RT-PCR and sequencing. Fragments of exon 5 and a part of the flanking intron 5 region (g.7679 –g.8073) were amplified of patients' DNA and cloned into the exon trap-vector pET01. Different vector constructs containing minigenes of the wild type (g.IVS5+78G) or mutant form (g.IVS5+78A) and the corresponding minigenes with an “optimized” naturally-occurring donor splice site in position +5 respectively were transfected into HEK293 cells. The expressed RNA was isolated and characterized. Consensus Values (CV) for all donor splice sites were calculated using a splice site detection tool according Shapiro and Senapathy (1987). The RT-PCR analysis in patients indicate that the novel variation g.IVS5+78G>A in intron 5 created an aberrant splice site in position 79bp downstream of exon 5 even though the naturally-occurring donor-splice-site of exon 5 is not abolished. An insertion of 79bp of intron 5 into the mRNA leads to a frame shift and predicts a premature termination 11 codons past the last unaltered codon. Minigenes include the naturally-occurring splice site and the variation g.IVS5+78A used exclusively the aberrant splice position 79bp downstream of exon 5 whereas wild type minigenes with the naturally-occurring splice site and the wild type form g.IVS5+78G produced normally spliced mRNA. In a following experiment the “naturally-occurring splice site” of exon 5 was optimized by the additional substitution g.IVS5+5C>G which increased their CV from 76.6 to 90.9 compared to the CV of the novel mutant g.IVS5+78A of 80.3. In presence of both mutations (g.IVS5+5G and g.IVS5+78A) only normal spliced mRNA was expressed of this minigene. In this construct the mutation g.IVS5+78G>A was without importance for the mRNA splicing. The results of the in vitro experiments demonstrated, that the Consensus Values (CV) seems to be an important factor for the selection of donor splice sites in the F7 gene. In the “Greifswald Registry FVII Deficiency” 26 different splice site variations in F7 gene were identified (Tab. 1). The atypical splice site variation g.IVS5+78G>A, +78bp downstream of exon 5 was present in 7 FVIID patients from Sweden and Germany in different genotypes. This novel F7 gene mutation g.IVS5+78G>A creates an aberrant splice site in position +79 of intron 5 and predicts premature termination. RNA analysis and expression studies demonstrated, that this novel F7 gene lesion is a type I mutation with low FVII:C and FVII: Ag levels and is the basis defect in 7 FVIID patients of the “Greifswald Registry FVII Deficiency”. Tab. 1 26 different intronic F7 gene mutations analysed in FVII deficiency patients of the “Greifswald Registry FVII Deficiency” Intron Acceptor splice site Intron Donor splice site 1b g.IVS1b-11G>A 1a g.IVS1a+5G>A 1b *g.IVS1b8del14bp 1a *g.IVS1a+6T>G 1b *g.IVS1b-3C>G 1a *g.IVS1a+8C>T 2 *g.IVS2-3C>G 2 g.IVS2+1G>A 3 g.IVS3-1G>A 2 *g.IVS2+1G>T 3 *g-IVS3-1G>T 2 *g.IVS2+1G>C 4 *g.IVS4-7T>G 2 *g.IVS2+1delG 7 *g.IVS7-10T>C 2 g.IVS2+5G>T 7 *g.IVS7-3C>G 3 *g.IVS3+1G>T 7 *g.IVS7-1G>A 4 g.IVS4+1G>A 5 *g.IVS5+78G>A 6 *g.IVS6+1G>A 6 g.IVS6+1G>T 6 *g.IVS6+3A>G 7 *g.IVS7+1G>A 7 g.IVS7+3_6 del4bp * novel mutations (HGMD Factor 7 Database, 2009 /http://www.hgmd.org) Disclosures: No relevant conflicts of interest to declare.

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