Abstract |
The common prothrombin gene cleavage site mutation 20210G>A is associated with elevated prothrombin levels and thrombosis. The pathomechanism of the 20210G>A mutation was explained by increased mRNA formation and/or more efficient translation. Human studies also showed an influence of the intronic 19911A>G polymorphism on prothrombin activity. We established HepG2 cell lines stably transfected with prothrombin mini-genes containing the last 2 prothrombin exons, the last intron, 3' untranslated region (UTR), and flanking sequence. The highest mRNA expression and protein activity resulted from the mutant haplotype 19911A-20210A. Haplotypes with wild-type cleavage site (19911A-20210G, 19911G-20210G) also differed significantly as a consequence of the intronic 19911 mutation; the 19911G-20210G haplotype showed lower expression than the 19911A-20210G haplotype, whereas previous clinical studies have reported elevated prothrombin activity with the 19911G-20210G haplotype. The cleavage site pattern was homogeneous with 20210A, which may cause a favorable intracellular processing, and heterogeneous with 20210G. In an independent assay for splicing efficiency, 19911G showed about 30% higher efficiency than 19911A. We conclude that the intronic 19911A>G single nucleotide polymorphism is itself functional and changes splicing efficiency by altering a known functional pentamer motif. Further studies are needed to define the value of additional prothrombin 19911 genotyping for thrombophilia screening, especially in cases heterozygous for 20210G>A.
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Authors | Nicolas von Ahsen, Michael Oellerich |
Journal | Blood
(Blood)
Vol. 103
Issue 2
Pg. 586-93
(Jan 15 2004)
ISSN: 0006-4971 [Print] United States |
PMID | 14504098
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Codon, Nonsense
- DNA Primers
- Peptide Fragments
- RNA, Messenger
- Prothrombin
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Topics |
- Alternative Splicing
- Amino Acid Sequence
- Animals
- Base Sequence
- Cell Line
- Codon, Nonsense
(genetics)
- DNA Primers
- Enzyme-Linked Immunosorbent Assay
- Genes, Reporter
- Genetic Variation
- Humans
- Introns
(genetics)
- Peptide Fragments
(chemistry)
- Polymorphism, Single Nucleotide
- Prothrombin
(chemistry, genetics)
- RNA, Messenger
(genetics)
- Restriction Mapping
- Thrombophilia
(genetics)
- Transcription, Genetic
(genetics)
- Transfection
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