Imperial College London

DrCarolynMillar

Faculty of MedicineDepartment of Immunology and Inflammation

Honorary Clinical Senior Lecturer
 
 
 
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Contact

 

+44 (0)20 3313 2153c.millar

 
 
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Location

 

Commonwealth BuildingHammersmith Campus

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Summary

 

Publications

Citation

BibTex format

@article{Westbury:2017:10.1182/blood-2017-03-776773,
author = {Westbury, SK and Canault, M and Greene, D and Bermejo, E and Hanlon, K and Lambert, MP and Millar, CM and Nurden, P and Obaji, SG and Revel-Vilk, S and Van, Geet C and Downes, K and Papadia, S and Tuna, S and Watt, C and Freson, K and Laffan, MA and Ouwehand, WH and Alessi, M-C and Turro, E and Mumford, AD},
doi = {10.1182/blood-2017-03-776773},
journal = {Blood},
pages = {1026--1030},
title = {Expanded repertoire of RASGRP2 variants responsible for platelet dysfunction and severe bleeding},
url = {http://dx.doi.org/10.1182/blood-2017-03-776773},
volume = {130},
year = {2017}
}

RIS format (EndNote, RefMan)

TY  - JOUR
AB - Heritable platelet function disorders (PFDs) are genetically heterogeneous and poorly characterised. Pathogenic variants in RASGRP2, which encodes calcium and diacylglycerol-regulated guanine exchange factor I (CalDAG-GEFI), have been reported previously in three pedigrees with bleeding and reduced platelet aggregation responses. To better define the phenotype associated with pathogenic RASGRP2 variants, we compared high-throughput sequencing and phenotype data from 2,042 cases in pedigrees with unexplained bleeding or platelet disorders to data from 5,422 controls. Eleven cases harboured 11 different, previously unreported RASGRP2 variants that were biallelic and likely pathogenic. The variants included five high-impact variants predicted to prevent CalDAG-GEFI expression and six missense variants affecting the CalDAG-GEFI CDC25 domain, which mediates Rap1 activation during platelet inside-out αIIbβ3 signalling. Cases with biallelic RASGRP2 variants had abnormal mucocutaneous, surgical and dental bleeding from childhood, requiring at least one blood or platelet transfusion in 78% of cases. Platelets displayed reduced aggregation in response to ADP and epinephrine, but variable aggregation defects with other agonists. There were no other consistent clinical or laboratory features. These data enable definition of human CalDAG-GEFI deficiency as a non-syndromic, recessive PFD associated with a moderate or severe bleeding phenotype and complex defects in platelet aggregation.
AU - Westbury,SK
AU - Canault,M
AU - Greene,D
AU - Bermejo,E
AU - Hanlon,K
AU - Lambert,MP
AU - Millar,CM
AU - Nurden,P
AU - Obaji,SG
AU - Revel-Vilk,S
AU - Van,Geet C
AU - Downes,K
AU - Papadia,S
AU - Tuna,S
AU - Watt,C
AU - Freson,K
AU - Laffan,MA
AU - Ouwehand,WH
AU - Alessi,M-C
AU - Turro,E
AU - Mumford,AD
DO - 10.1182/blood-2017-03-776773
EP - 1030
PY - 2017///
SN - 1528-0020
SP - 1026
TI - Expanded repertoire of RASGRP2 variants responsible for platelet dysfunction and severe bleeding
T2 - Blood
UR - http://dx.doi.org/10.1182/blood-2017-03-776773
UR - http://hdl.handle.net/10044/1/53259
VL - 130
ER -