Thrombosis and Haemostasis, Table of Contents

Thromb Haemost 2007; 98(06): 1165-1169
DOI: 10.1160/TH07-02-0125

Rapid and Short Communication

Schattauer GmbH

A nonstop mutation in the factor (F)X gene of a severely haemorrhagic patient with complete absence of coagulation FX

Afshin Ameri^*

¹Department of Pediatrics, Division of Hematology and Oncology, Medical College of Georgia, Augusta, Georgia, USA

,

Deepa K. Machiah^*

²Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia, USA

,

Thuy T. Tran^*

²Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia, USA

,

Cynthia Channell

²Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia, USA

,

Valerie Crenshaw

¹Department of Pediatrics, Division of Hematology and Oncology, Medical College of Georgia, Augusta, Georgia, USA

,

Karl Fernstrom

²Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia, USA

,

Manana Khachidze

²Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia, USA

,

Alexander Duncan

²Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia, USA

,

Sebastien Fuchs

²Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia, USA

,

Tom E. Howard

²Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia, USA

⁴Current address: Department of Pathology and Laboratory Medicine, Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, California, USA

› Author Affiliations

Summary

We identified a previously unknown mutation by sequencing the factor (F)X gene in a severely haemorrhagic 14-year-old maleAfrican-American individual with undetectable plasma FX-activity and -antigen levels. This mutation, called F10-Augusta, was homozygote and is a combination of an 8bp insertion in flanking 3’-genomic-DNA and a 5bp terminal exon-8 deletion involving codons 437 and 438. Sequencing of RT-PCR and 3’-RACE products showed that the F10-Augusta transcript is normally processed but lacks an in-frame stop codon. An allele specific 3’-RACE-based RFLP assay demonstrated that the steady-state concentration of the mutant transcript was markedly lower than that of the wild-type message in total-RNA samples from the patient’s unaffected heterozygous parents. The recently discovered nonstop decay mechanism, a component pathway of the mRNA surveillance system, is a possible explanation for the reduced concentration of the mutant FX transcript. This is the first report implying such a mechanism in the pathogenesis of inherited bleeding disorders.

Keywords

Keywords

Autosomal recessive - congenital bleeding disorder - mRNA surveillance - F10-Augusta

References
1 Mannucci PM, Duga S, Peyvandi F. Recessively inherited coagulation disorders. Blood 2004; 104: 1243-1252.
2 Cooper DN, Millar DS, Wacey A. et al. Inherited factor X deficiency: molecular genetics and pathophysiology. Thromb Haemost 1997; 78: 161-172.
3 Leytus SP, Foster DC, Kurachi K. et al. Gene for human factor X: a blood coagulation factor whose gene organization is essentially identical with that of factor IX and protein C. Biochemistry 1986; 25: 5098-5102.
4 Rieder MJ, Armel TZ, Carrington DP. et al. SeattleSNPs. NHLBI HL66682 Program for Genomic Applications, UW-FHCRC, Seattle, WA, USA (URL: http://pga.gs.washington.edu ). 2002.
5 Khachidze M, Buil A, Viel KR. et al. Genetic determinants of normal variation in coagulation factor (F) IX levels: genome-wide scan and examination of the FIX structural gene. J Thromb Haemost 2006; 4: 1537-1545.
6 Karolchik D, Baertsch R, Diekhans M. et al. The UCSC Genome Browser Database. Nucl Acids Res 2003; 31: 51-54.
7 Pruitt KD, Tatusova T, Maglott DR. NCBI Reference Sequence (RefSeq): a curated non-redundant sequence database of genomes, transcripts and proteins. Nucleic Acids Res 2005; 33: D501-504.
8 Wahle E, Ruegsegger U. 3‘-End processing of premRNA in eukaryotes. FEMS Microbiol Rev 1999; 23: 277-295.
9 Shapiro MB, Senapathy P. RNA splice junctions of different classes of eukaryotes: sequence statistics and functional implications in gene expression. Nucleic Acids Res 1987; 15: 7155-7174.
10 Frischmeyer PA, van Hoof A, O’Donnell K. et al. An mRNA surveillance mechanism that eliminates transcripts lacking termination codons. Science 2002; 295: 2258-2261.
11 van Hoof A, Frischmeyer PA, Dietz HC. et al. Exosome- mediated recognition and degradation of mRNAs lacking a termination codon. Science 2002; 295: 2262-2264.
12 Akimitsu N, Tanaka J, Pelletier J. Translation of nonSTOP mRNA is repressed post-initiation in mammalian cells. Embo J 2007; 26: 2327-2338.
13 Inada T, Aiba H. Translation of aberrant mRNAs lacking a termination codon or with a shortened 3‘-UTR is repressed after initiation in yeast. Embo J 2005; 24: 1584-1595.
14 Ito-Harashima S, Kuroha K, Tatematsu T. et al. Translation of the poly(A) tail plays crucial roles in nonstop mRNA surveillance via translation repression and protein destabilization by proteasome in yeast. Genes Dev 2007; 21: 519-524.
15 Li X, Hirano R, Tagami H. et al. Protein tagging at rare codons is caused by tmRNA action at the 3’ end of nonstop mRNA generated in response to ribosome stalling. RNA 2006; 12: 248-255.