Test Database

Description

Analysis of the SERPINC1 gene by PCR amplification and sequencing of the coding region and splice junctions is the gold standard approach. Dosage analysis, via MLPA, is available as a second line test where gross deletions/ insertions are suspected.

Clinical details

Heritable antithrombin deficiency is an autosomal dominant disorder caused by mutations in the SERPINC1 gene. Heterozygous deficiency is usually associated with Antithrombin activity levels in the range of 40-60% of normal. Homozygosity is very rare and is often fatal in utero. Deficiencies are characterised as either Type I (a quantitative deficiency) or Type II (a qualitative deficiency). Type II deficiency is then further classified depending on whether the causative mutation affects the reactive site , the heparin binding domain or the reactive loop site. Phenotypic assays for Antithrombin deficiency can be complicated by acute clinical presentation and therapy, and so molecular confirmation of Antithrombin deficiency is of clinical utility.

Related condition

Antithrombin deficiency. Venous thromboembolism, typically DVT and PE. Heparin binding defects may be resistant to the anticoagulant effects of heparin and so are clinically important.

Reference range

n/a

Units

n/a

Synonyms

SERPINC1 AT Antithrombin deficiency Thrombosis DVT PE

Testing site

Synnovis : Blood Sciences : St Thomas' Hospital

Laboratory

Molecular Haemostasis