RESEARCH Open Access
First report of molecular diagnosis of Tunisian
hemophiliacs A: Identification of 8 novel
causative mutations
Hejer Elmahmoudi
1*
, Houssein Khodjet-el-khil
1
, Edvard Wigren
2
, Asma Jlizi
1
, Kaouther Zahra
3
, Dorothé Pellechia
4
,
Christine Vinciguerra
4
, Balkis Meddeb
3
, Amel Ben Ammar Elggaaied
1
and Emna Gouider
3
Abstract
Introduction: Hemophilia A is an X linked recessive hemorrhagic disorder caused by mutations in the F8 gene
that lead to qualitative and/or quantitative deficiencies of coagulation factor VIII (FVIII). Molecular diagnosis of
hemophilia A is challenging because of the high number of different causative mutations that are distributed
throughout the large F8 gene. Molecular studies of these mutations are essential in order to reinforce our
understanding of their pathogenic effect responsible for the disorder.
Aim: In this study we have performed molecular analysis of 28 Tunisian hemophilia A patients and analyzed the
F8 mutation spectrum.
Methods: We screened the presence of intron 22 and intron 1 inversion in severe hemophilia A patients
by southern blotting and polymerase chain reaction (PCR). Detection of point mutations was performed by
dHPLC/sequencing of the coding F8 gene region. We predict the potential functional consequences of novel
missense mutations with bioinformatics approaches and mapping of their spatial positions on the available
FVIII 3D structure.
Results: We identified 23 different mutations in 28 Tunisian hemophilia A patients belonging to 22 unrelated
families. The identified mutations included 5 intron 22 inversions, 7 insertions, 4 deletions and 7 substitutions.
In total 18 point mutations were identified, of which 9 are located in exon 14, the most mutated exonic
sequence in the F8 gene. Among the 23 mutations, 8 are novel and not deposited in the HAMSTeRS database
nor described in recently published articles.
Conclusion: The mutation spectrum of Tunisian hemophilia A patients is heterogeneous with the presence
of some characteristic features.
Virtual slides: The virtual slide(s) for this article can be found here:
http://www.diagnosticpathology.diagnomx.eu/vs/1693269827490715
Keywords: Hemophilia A, Mutations, Intron 22 inversion, Intron 1 inversion, Inhibitors, Molecular analysis, Tunisia
* Correspondence: hejer.abdalah@gmail.com
1
Laboratory of Genetics, Immunology and Human Pathologies, Tunis, Tunisia
Full list of author information is available at the end of the article
© 2012 Elmahmoudi et al.; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the
Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use,
distribution, and reproduction in any medium, provided the original work is properly cited.
Elmahmoudi et al. Diagnostic Pathology 2012, 7:93
http://www.diagnosticpathology.org/content/7/1/93