Analysis of mRNA in hemophilia A patients with undetectable mutations reveals normal splicing in the factor VIII gene
- PMID: 15670040
- DOI: 10.1111/j.1538-7836.2005.01140.x
Analysis of mRNA in hemophilia A patients with undetectable mutations reveals normal splicing in the factor VIII gene
Abstract
Background: haemophilia A (HA) is characterized by partial or total deficiency of factor VIII (FVIII) protein activity. It is caused by a broad spectrum of mutations in the FVIII gene. Despite tremendous improvements in mutation screening methods, in about 2% of HA patients no DNA change could be found, even after sequencing the whole coding part of the FVIII gene including the flanking splice sites, as well as the promotor and the 3' UTR regions.
Objectives, patients and methods: In the present study we performed a detailed RNA analysis of three groups of patients. The first included control patients with known splicing defects, the second included two patients with already identified nucleotide changes close to splicing sites, that could potentially alter the normal splicing process, and a third group of 11 unrelated patients whose genomic DNA have already been screened for mutations by DHPLC and direct sequencing with no mutation being identified.
Results: Both candidate splice site mutations were shown to result in either skipping or alternative splicing of at least one exon, therefore these DNA changes must be considered as causal for the patients' HA phenotype. In contrast, no abnormalities on the RNA level were observed in any of 11 unrelated patients without mutations in the FVIII gene.
Conclusions: These findings exclude mutations that could be located deep in the introns and affecting either normal splicing or lead to mechanisms causing some unknown rearrangements of the FVIII gene. In fact, our results point to the presence of still unknown factor(s) causing HA, which might be either allelic or in the close proximity of the FVIII gene or non-allelic associated with other genetic loci that are involved in the processing of the FVIII protein.
Similar articles
-
Characterization of a splicing mutation in the factor VIII gene at the RNA level.Hum Genet. 1995 Jan;95(1):109-11. doi: 10.1007/BF00225086. Hum Genet. 1995. PMID: 7814012
-
Molecular characterization of ten F8 splicing mutations in RNA isolated from patient's leucocytes: assessment of in silico prediction tools accuracy.Haemophilia. 2015 Mar;21(2):249-257. doi: 10.1111/hae.12562. Epub 2015 Feb 5. Haemophilia. 2015. PMID: 25652415
-
A novel splicing acceptor mutation of the factor VIII gene producing skipping of exon 25.Ann Hematol. 2003 Mar;82(3):175-7. doi: 10.1007/s00277-002-0592-y. Epub 2003 Feb 13. Ann Hematol. 2003. PMID: 12634951
-
F8 genetic analysis strategies when standard approaches fail.Hamostaseologie. 2014;34(2):167-73. doi: 10.5482/HAMO-13-08-0043. Epub 2013 Dec 3. Hamostaseologie. 2014. PMID: 24296544 Review.
-
[Molecular genetics of hemophilia A].Medicina (B Aires). 1996;56(5 Pt 1):509-17. Medicina (B Aires). 1996. PMID: 9239887 Review. Spanish.
Cited by
-
Aberrant X chromosomal rearrangement through multi-step template switching during sister chromatid formation in a patient with severe hemophilia A.Mol Genet Genomic Med. 2020 Sep;8(9):e1390. doi: 10.1002/mgg3.1390. Epub 2020 Jul 5. Mol Genet Genomic Med. 2020. PMID: 32627361 Free PMC article.
-
Evaluation of von Willebrand factor phenotypes and genotypes in Hemophilia A patients with and without identified F8 mutations.J Thromb Haemost. 2015 Jun;13(6):1036-42. doi: 10.1111/jth.12902. Epub 2015 May 9. J Thromb Haemost. 2015. PMID: 25780857 Free PMC article.
-
A Foundational Study for Normal F8-Containing Mouse Models for the miRNA Regulation of Hemophilia A: Identification and Analysis of Mouse miRNAs that Downregulate the Murine F8 Gene.Int J Mol Sci. 2020 Aug 6;21(16):5621. doi: 10.3390/ijms21165621. Int J Mol Sci. 2020. PMID: 32781510 Free PMC article.
-
Molecular Analysis of Factor VIII and Factor IX Genes in Hemophilia Patients: Identification of Novel Mutations and Molecular Dynamics Studies.J Clin Med Res. 2017 Apr;9(4):317-331. doi: 10.14740/jocmr2876w. Epub 2017 Feb 21. J Clin Med Res. 2017. PMID: 28270892 Free PMC article.
-
Mutations in intron 1 and intron 22 inversion negative haemophilia A patients from Western India.PLoS One. 2014 May 20;9(5):e97337. doi: 10.1371/journal.pone.0097337. eCollection 2014. PLoS One. 2014. PMID: 24845853 Free PMC article. Clinical Trial.
Publication types
MeSH terms
Substances
LinkOut - more resources
Full Text Sources
Medical