PROS1 mutation screen

Analysis of the PROS1 gene by PCR amplification and sequencing of the coding region and splice junctions. Dosage analysis, via MLPA, is available as a second line test where gross deletions/ insertions are suspected.
Clinical details: 
Protein S is a co-factor for activated protein C and its deficiency leads to an increased risk of thrombophilia. Venous thrombosis occurs in 60-80% of patients heterozygous for protein S deficiency, generally before 40-45 years of age. It is an autosomal dominant disorder, caused by mutations in the PROS1 gene, with an estimated frequency of approximately 1 in 700. Homozygosity is very rare and results in life-threatening neonatal purpura fulminans.
Protein S deficiency is sub-classified as Type I (Quantitative), Type II (Qualitative) and Type III (low free PS / normal total PS). Mutations in PROS1 are less frequently identified in phenotypic Type III patients than in Type I and in some cases a lack of linkage to the PROS1 locus has been demonstrated.
Reference range: 


Synonyms or keywords: 
PROS1 Protein S deficiency Thrombophilia Thrombosis DVT PE
Sample type and Volume required: 
1 x Edta
Call in advance: 
Turnaround time: 
6 weeks
Storage and transport: 
transport at ambient temperature
Molecular Haemostasis Laboratory at St Thomas'
020 7188 2798
Haemostasis and Thrombosis
North Wing - 4th floor
St Thomas' Hospital
Westminster Bridge Road
London SE1 7EH

Laboratory opening times
Monday - Friday 09.00 - 17.00
For clinical advice or interpretation of results, please contact the laboratory in the first instance.

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Last updated: 14/03/2017