Microsatellite (GT)n repeats and SNPs in the von Willebrand factor gene promoter do not influence circulating von Willebrand factor levels under normal conditions

2009 ◽  
Vol 101 (02) ◽  
pp. 298-304 ◽  
Author(s):  
Viviana Daidone ◽  
Maria Grazia Cattini ◽  
Elena Pontara ◽  
Francesca Sartorello ◽  
Lisa Gallinaro ◽  
...  
Keyword(s):  
Von Willebrand Factor ◽  
Polymorphic Locus ◽  
Gene Promoter ◽  
Strong Linkage Disequilibrium ◽  
Common Variants ◽  
Normal Individuals ◽  
Haplotype 1 ◽  
Von Willebrand ◽  
Willebrand Factor ◽  
Promoter Haplotype

SummaryVon Willebrand factor (VWF) levels vary considerably in normal individuals, influenced by inherited and acquired modulators. ABO blood group is the major inherited determinant of VWF levels, but a role has also been attributed to the VWF gene promoter, haplotype 1 (-3268G/-2709C/-2661A/-2527G) being associated with higher VWF levels than haplotype 2 (-3268C/-2709T/-2661G/-2527A), and the polymorphic locus (GT)n modulating the shear stress-induced activation of the VWF promoter. We characterized the (GT)n of the VWF promoter in 394 healthy individuals and assessed whether its variable length influenced VWF levels in normal conditions. (GT)n proved highly polymorphic, with alleles from 15 to 24 repeats long. (GT)21 and (GT)19 were the most common variants (37.4% and 34.4%, respectively). Short GT repeats (15–19) segregated mainly with haplotype 1, long GT repeats (20–24) with haplotype 2 (p<0.0001). The number of GT repeats did not correlate with VWF levels, nor did such levels correlate with haplotypes 1 and 2, considered alone or in association with the (GT)n locus. We conclude that (GT)n and -3268/-2709/-2661/-2527 loci are in strong linkage disequilibrium. This polymorphic region of the VWF promoter does not affect VWF levels under normal conditions, though it might represent an environmentally activable VWF regulation site.

Variation at the von Willebrand Factor (vWF) Gene Locus Is Associated With Plasma vWF:Ag Levels: Identification of Three Novel Single Nucleotide Polymorphisms in the vWF Gene Promoter

Blood ◽  
1999 ◽  
Vol 93 (12) ◽  
pp. 4277-4283 ◽  
Author(s):  
Angela M. Keightley ◽  
Y. Miu Lam ◽  
Jolene N. Brady ◽  
Cherie L. Cameron ◽  
David Lillicrap
Keyword(s):  
Single Nucleotide Polymorphisms ◽  
Von Willebrand Factor ◽  
Gene Locus ◽  
Strong Linkage Disequilibrium ◽  
Nucleotide Polymorphisms ◽  
Polymorphic Variation ◽  
Single Nucleotide ◽  
Haplotype 1 ◽  
Von Willebrand ◽  
Willebrand Factor

Abstract Both genetic and environmental factors contribute to the normal population variability of plasma von Willebrand Factor (vWF) levels, however, regulatory mechanisms at the vWF gene locus itself have not yet been identified. We have investigated the association between polymorphic variation in the 5′-regulatory region of the vWF gene and levels of plasma vWF:Ag in a study of 261 group O blood donors. Three novel single nucleotide polymorphisms (SNPs) were identified in the vWF promoter: C/T at -1234, A/G at -1185, and G/A at -1051. These SNPs had identical allele frequencies of 0.36 for the -1234C, -1185A, and -1051G alleles and 0.64 for the -1234T, -1185G, and -1051A alleles and were in strong linkage disequilibrium. In fact, these polymorphisms segregated as two distinct haplotypes: -1234C/-1185A/-1051G (haplotype 1) and -1234T/-1185G/-1051A (haplotype 2) with 12.6% of subjects homozygous for haplotype 1, 40.6% homozygous for haplotype 2, and 42.5% of subjects heterozygous for both haplotypes. Only 4.3% of individuals had other genotypes. A significant association between promoter genotype and level of plasma vWF:Ag was established (analysis of covariance [ANCOVA], P = .008; Kruskal-Wallis test,P = .006); individuals with the CC/AA/GG genotype had the highest mean vWF:Ag levels (0.962 U/mL), intermediate values of vWF:Ag (0.867 U/mL) were observed for heterozygotes (CT/AG/GA), and those with the TT/GG/AA genotype had the lowest mean plasma vWF:Ag levels (0.776 U/mL). Interestingly, when the sample was subgrouped according to age, the significant association between promoter genotype and plasma vWF:Ag level was accentuated in subjects &gt; 40 years of age (analysis of variance [ANOVA], P = .003; Kruskal-Wallis test, P= .001), but was not maintained for subjects ≤ 40 years of age (ANOVA, P &gt; .4; Kruskal-Wallis test, P &gt; .4). In the former subgroup, mean levels of plasma vWF:Ag for subjects with the CC/AA/GG, CT/AG/GA, and TT/GG/AA genotypes were 1.075, 0.954, and 0.794 U/mL, respectively. By searching a transcription factor binding site profile database, these polymorphic sequences were predicted to interact with several transcription factors expressed in endothelial cells, including Sp1, GATA-2, c-Ets, and NFκB. Furthermore, the binding sites at the -1234 and -1051 SNPs appeared to indicate allelic preferences for some of these proteins. Electrophoretic mobility shift assays (EMSAs) performed with recombinant human NFκB p50 showed preferential binding of the -1234T allele (confirmed by supershift EMSAs), and EMSAs using bovine aortic endothelial cell (BAEC) nuclear extracts produced specific binding of a nuclear protein to the -1051A allele, but not the -1051G allele. These findings suggest that circulating levels of vWF:Ag may be determined, at least in part, by polymorphic variation in the promoter region of the vWF gene, and that this association may be mediated by differential binding of nuclear proteins involved in the regulation of vWF gene expression.

Variation at the von Willebrand Factor (vWF) Gene Locus Is Associated With Plasma vWF:Ag Levels: Identification of Three Novel Single Nucleotide Polymorphisms in the vWF Gene Promoter

Blood ◽  
1999 ◽  
Vol 93 (12) ◽  
pp. 4277-4283 ◽  
Author(s):  
Angela M. Keightley ◽  
Y. Miu Lam ◽  
Jolene N. Brady ◽  
Cherie L. Cameron ◽  
David Lillicrap
Keyword(s):  
Single Nucleotide Polymorphisms ◽  
Von Willebrand Factor ◽  
Gene Locus ◽  
Strong Linkage Disequilibrium ◽  
Nucleotide Polymorphisms ◽  
Polymorphic Variation ◽  
Single Nucleotide ◽  
Haplotype 1 ◽  
Von Willebrand ◽  
Willebrand Factor

Both genetic and environmental factors contribute to the normal population variability of plasma von Willebrand Factor (vWF) levels, however, regulatory mechanisms at the vWF gene locus itself have not yet been identified. We have investigated the association between polymorphic variation in the 5′-regulatory region of the vWF gene and levels of plasma vWF:Ag in a study of 261 group O blood donors. Three novel single nucleotide polymorphisms (SNPs) were identified in the vWF promoter: C/T at -1234, A/G at -1185, and G/A at -1051. These SNPs had identical allele frequencies of 0.36 for the -1234C, -1185A, and -1051G alleles and 0.64 for the -1234T, -1185G, and -1051A alleles and were in strong linkage disequilibrium. In fact, these polymorphisms segregated as two distinct haplotypes: -1234C/-1185A/-1051G (haplotype 1) and -1234T/-1185G/-1051A (haplotype 2) with 12.6% of subjects homozygous for haplotype 1, 40.6% homozygous for haplotype 2, and 42.5% of subjects heterozygous for both haplotypes. Only 4.3% of individuals had other genotypes. A significant association between promoter genotype and level of plasma vWF:Ag was established (analysis of covariance [ANCOVA], P = .008; Kruskal-Wallis test,P = .006); individuals with the CC/AA/GG genotype had the highest mean vWF:Ag levels (0.962 U/mL), intermediate values of vWF:Ag (0.867 U/mL) were observed for heterozygotes (CT/AG/GA), and those with the TT/GG/AA genotype had the lowest mean plasma vWF:Ag levels (0.776 U/mL). Interestingly, when the sample was subgrouped according to age, the significant association between promoter genotype and plasma vWF:Ag level was accentuated in subjects > 40 years of age (analysis of variance [ANOVA], P = .003; Kruskal-Wallis test, P= .001), but was not maintained for subjects ≤ 40 years of age (ANOVA, P > .4; Kruskal-Wallis test, P > .4). In the former subgroup, mean levels of plasma vWF:Ag for subjects with the CC/AA/GG, CT/AG/GA, and TT/GG/AA genotypes were 1.075, 0.954, and 0.794 U/mL, respectively. By searching a transcription factor binding site profile database, these polymorphic sequences were predicted to interact with several transcription factors expressed in endothelial cells, including Sp1, GATA-2, c-Ets, and NFκB. Furthermore, the binding sites at the -1234 and -1051 SNPs appeared to indicate allelic preferences for some of these proteins. Electrophoretic mobility shift assays (EMSAs) performed with recombinant human NFκB p50 showed preferential binding of the -1234T allele (confirmed by supershift EMSAs), and EMSAs using bovine aortic endothelial cell (BAEC) nuclear extracts produced specific binding of a nuclear protein to the -1051A allele, but not the -1051G allele. These findings suggest that circulating levels of vWF:Ag may be determined, at least in part, by polymorphic variation in the promoter region of the vWF gene, and that this association may be mediated by differential binding of nuclear proteins involved in the regulation of vWF gene expression.

The Interaction of Botrocetin with Normal or Variant von Willebrand Factor (Types IIA and IIB) and Its Inhibition by Monoclonal Antibodies that Block Receptor Binding

1992 ◽  
Vol 68 (04) ◽  
pp. 464-469 ◽  
Author(s):  
Y Fujimura ◽  
S Miyata ◽  
S Nishida ◽  
S Miura ◽  
M Kaneda ◽  
...  
Keyword(s):  
Monoclonal Antibodies ◽  
Von Willebrand Factor ◽  
Binding Activity ◽  
Von Willebrand Disease ◽  
Platelet Glycoprotein ◽  
Normal Individuals ◽  
Rag 1 ◽  
The One ◽  
Von Willebrand ◽  
Willebrand Factor

SummaryWe have recently shown the existence of two distinct forms of botrocetin (one-chain and two-chain), and demonstrated that the two-chain species is approximately 30 times more active than the one-chain in promoting von Willebrand factor (vWF) binding to platelet glycoprotein (GP) Ib. The N-terminal sequence of two-chain botrocetin is highly homologous to sea-urchin Echinoidin and other Ca2+-dependent lectins (Fujimura et al., Biochemistry 1991; 30: 1957–64).Present data indicate that purified two-chain botrocetin binds to vWF from plasmas of patients with type IIA or IIB von Willebrand disease and its interaction is indistinguishable from that with vWF from normal individuals. However, an “activated complex” formed between botrocetin and IIB vWF expresses an enhanced biological activity for binding to GP Ib whereas the complex with IIA vWF has a decreased binding activity. Among several anti-vWF monoclonal antibodies (MoAbs) which inhibit ristocetin-induced platelet aggregation and/or vWF binding to GPIb, only two MoAbs (NMC-4 and RFF-VIII RAG:1) abolished direct binding between purified botrocetin and vWF. This suggests that they recognize an epitope(s) on the vWF molecule in close proximity to the botrocetin binding site.

ABO Blood Group Genotype and Plasma von Willebrand Factor in Normal Individuals

Vox Sanguinis ◽  
1995 ◽  
Vol 68 (4) ◽  
pp. 236-240 ◽  
Author(s):  
Masayuki Shima ◽  
Yoshihiro Fujimura ◽  
Takayuki Nishiyama ◽  
Tomomi Tsujiuchi ◽  
Nobuhiro Narita ◽  
...  
Keyword(s):  
Blood Group ◽  
Von Willebrand Factor ◽  
Abo Blood Group ◽  
Normal Individuals ◽  
Von Willebrand ◽  
Willebrand Factor

scholarly journals The "Normandy" variant of von Willebrand disease: characterization of a point mutation in the von Willebrand factor gene

Blood ◽  
1991 ◽  
Vol 77 (9) ◽  
pp. 1937-1941 ◽  
Author(s):  
C Gaucher ◽  
S Jorieux ◽  
B Mercier ◽  
D Oufkir ◽  
C Mazurier
Keyword(s):  
Amino Acid ◽  
Point Mutation ◽  
Von Willebrand Factor ◽  
Binding Capacity ◽  
Von Willebrand Disease ◽  
Normal Individuals ◽  
New Variant ◽  
Functional Defect ◽  
Von Willebrand ◽  
Willebrand Factor

Abstract We previously reported a functional defect of von Willebrand factor (vWF) in a new variant of von Willebrand disease (vWD) tentatively named vWD “Normandy.” The present work has attempted to characterize the molecular abnormality of this vWF that fails to bind factor VIII (FVIII). The immunopurified vWF from normal and patient's plasma were digested by trypsin and the resulting peptides were compared. The electrophoresis of ““vWF Normandy” showed a shift in the band corresponding to a polypeptide from amino acid 1 to 272. Consequently, we performed the molecular analysis of the portion of the vWF gene of this patient encoding this amino acid sequence. Exons 18–24 were amplified by the use of polymerase chain reaction and their nucleotide sequences corresponding to 1.8 kb were determined. Our analysis showed a point mutation C to T at codon 791, resulting in the substitution of Methionine for Threonine at position 28 of the mature vWF subunit. Because this nucleotide substitution destroyed a Mae II restriction site, this mutation was conveniently sought in various individual DNAs. The patterns obtained were consistent with the homozygous and heterozygous state of this mutation in the patient and in her son, respectively, and with its absence in 28 normal individuals. We conclude that Threonine at position 28 in plasma vWF may be crucial for the conformation and FVIII-binding capacity of its cystine-rich N- terminal domain.

scholarly journals Influence of mutations and size of multimers in type II von Willebrand disease upon the function of von Willebrand factor

Blood ◽  
1994 ◽  
Vol 83 (12) ◽  
pp. 3553-3561 ◽  
Author(s):  
O Christophe ◽  
AS Ribba ◽  
D Baruch ◽  
B Obert ◽  
C Rouault ◽  
...  
Keyword(s):  
Von Willebrand Factor ◽  
Point Mutations ◽  
Von Willebrand Disease ◽  
Platelet Glycoprotein ◽  
Binding Assays ◽  
Normal Individuals ◽  
Binding Isotherms ◽  
Significant Difference ◽  
Von Willebrand ◽  
Willebrand Factor

Abstract We compared the properties of plasma von Willebrand factor (vWF) from normal individuals and from two patients with type IIA (Glu875Lys) and type IIB (duplication of Met 540) von Willebrand disease (vWD) with the corresponding fully multimerized recombinant proteins. We included cryosupernatant from normal human plasma and type IIA plasma (Cys509Arg). Functions of vWF were analyzed by binding assays to platelets in the presence of ristocetin or botrocetin. Parameters of binding (number of binding sites per vWF subunit, and dissociation constant Kd) were quantitatively estimated from the binding isotherms of 125I-botrocetin or glycocalicin to vWF, independently of the size of the multimers. We found that ristocetin- or botrocetin-induced binding to platelets was correlated in all cases with the size of vWF multimers. In the absence of inducer, only type IIB rvWF Met-Met540 spontaneously bound to platelets. No significant difference of binding of purified botrocetin to vWF was found between normal and patients' plasma, or between wild-type rvWF (rvWF-WT) and rvWF-Lys875. In contrast, affinity of botrocetin for type IIB rvWF Met-Met540 was decreased. Botrocetin-induced binding of glycocalicin to vWF from all plasma and cryosupernatant was similar. Compared with rvWF-WT, binding of glycocalicin to rvWF-Lys875 was normal. In contrast, the affinity for type IIB rvWF Met-Met540 was 10-fold greater. Thus, our data suggest that, in the patients tested, the abnormal IIA phenotype results from the lack of large-sized multimers and is independent of the point mutations. In contrast, the type IIB mutation is directly involved by providing a conformation to the vWF subunits that allows the high molecular weight multimers to spontaneously interact with platelet glycoprotein Ib.

scholarly journals Proteolytic degradation of von Willebrand factor after DDAVP administration in normal individuals

Blood ◽  
1987 ◽  
Vol 70 (1) ◽  
pp. 173-176 ◽  
Author(s):  
J Batlle ◽  
MF Lopez-Fernandez ◽  
A Lopez-Borrasca ◽  
C Lopez-Berges ◽  
JA Dent ◽  
...  
Keyword(s):  
Von Willebrand Factor ◽  
Resting State ◽  
Relative Proportion ◽  
The Other ◽  
Proteolytic Degradation ◽  
Normal Individuals ◽  
Rapid Clearance ◽  
Von Willebrand ◽  
Willebrand Factor ◽  
Adult Volunteers

Abstract The infusion of 1-deamino-8-D-arginine vasopressin (DDAVP) in normal individuals is followed by an increase in factor VIII/von Willebrand factor (vWF) in plasma, by an increase in intensity of all sizes of multimers, and by the appearance of larger multimers of vWF than those seen in the resting state. Since the larger multimers are rapidly cleared and proteolysis is known to cause disaggregation of large multimers, we evaluated the degree of vWF proteolysis after DDAVP administration. DDAVP was infused into eight normal adult volunteers, and the relative proportions of the intact 225 kilodalton (kDa) subunit and the 189, 176, and 140 kDa vWF fragments were compared before and at different times after DDAVP infusion. The relative proportion of the 176 kDa fragment was increased, whereas that of the other species was decreased, thereby indicating that proteolytic fragmentation had occurred. However, plasmin did not appear to be responsible because the vWF fragments characteristically produced by this enzyme could not be detected. Concomitant analysis of vWF multimeric structure showed that these changes were accompanied by an increase in the relative proportion of the satellite bands, which suggests that they were proteolytically generated. Proteolysis may explain, at least in part, rapid clearance of larger vWF multimers released by DDAVP.

scholarly journals Quantification of perioperative changes in von Willebrand factor and factor VIII during elective orthopaedic surgery in normal individuals

Haemophilia ◽  
2013 ◽  
Vol 19 (5) ◽  
pp. 758-764 ◽  
Author(s):  
A. Kahlon ◽  
J. Grabell ◽  
A. Tuttle ◽  
D. Engen ◽  
W. Hopman ◽  
...  
Keyword(s):  
Factor Viii ◽  
Von Willebrand Factor ◽  
Orthopaedic Surgery ◽  
Normal Individuals ◽  
Von Willebrand ◽  
Willebrand Factor

scholarly journals Polymorphisms in von Willebrand factor gene promoter influence the glucocorticoid-induced increase in von Willebrand factor: the lesson learned from Cushing syndrome

2007 ◽  
Vol 140 (2) ◽  
pp. 230-235 ◽  
Author(s):  
Alessandra Casonato ◽  
Viviana Daidone ◽  
Francesca Sartorello ◽  
Nora Albiger ◽  
Chiara Romualdi ◽  
...  
Keyword(s):  
Von Willebrand Factor ◽  
Cushing Syndrome ◽  
Gene Promoter ◽  
Factor Gene ◽  
Von Willebrand ◽  
Willebrand Factor

scholarly journals Proteolytic degradation of von Willebrand factor after DDAVP administration in normal individuals

Blood ◽  
1987 ◽  
Vol 70 (1) ◽  
pp. 173-176 ◽  
Author(s):  
J Batlle ◽  
MF Lopez-Fernandez ◽  
A Lopez-Borrasca ◽  
C Lopez-Berges ◽  
JA Dent ◽  
...  
Keyword(s):  
Von Willebrand Factor ◽  
Resting State ◽  
Relative Proportion ◽  
The Other ◽  
Proteolytic Degradation ◽  
Normal Individuals ◽  
Rapid Clearance ◽  
Von Willebrand ◽  
Willebrand Factor ◽  
Adult Volunteers

The infusion of 1-deamino-8-D-arginine vasopressin (DDAVP) in normal individuals is followed by an increase in factor VIII/von Willebrand factor (vWF) in plasma, by an increase in intensity of all sizes of multimers, and by the appearance of larger multimers of vWF than those seen in the resting state. Since the larger multimers are rapidly cleared and proteolysis is known to cause disaggregation of large multimers, we evaluated the degree of vWF proteolysis after DDAVP administration. DDAVP was infused into eight normal adult volunteers, and the relative proportions of the intact 225 kilodalton (kDa) subunit and the 189, 176, and 140 kDa vWF fragments were compared before and at different times after DDAVP infusion. The relative proportion of the 176 kDa fragment was increased, whereas that of the other species was decreased, thereby indicating that proteolytic fragmentation had occurred. However, plasmin did not appear to be responsible because the vWF fragments characteristically produced by this enzyme could not be detected. Concomitant analysis of vWF multimeric structure showed that these changes were accompanied by an increase in the relative proportion of the satellite bands, which suggests that they were proteolytically generated. Proteolysis may explain, at least in part, rapid clearance of larger vWF multimers released by DDAVP.

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