Related Experiment Videos
Asymptomatic factor VII deficiency in African Americans
Eleanor S Pollak1, Theresa T Russell, Beverly Ptashkin
1Department of Pathology and Laboratory Medicine, University of Pennsylvania Medical Center, Philadelphia, PA, USA.
American Journal of Clinical Pathology
|June 7, 2006
Summary
Genetic analysis reveals a specific mutation (G to A nucleotide change) in Factor VII (FVII) causes deficiency in asymptomatic African Americans. This finding helps clarify laboratory results and avoid unnecessary treatments.
Area of Science:
- Genetics
- Hematology
- Molecular Biology
Background:
- Factor VII (FVII) deficiency is often asymptomatic in African Americans.
- The genetic basis for FVII deficiency in this population remained largely uncharacterized.
- Accurate diagnosis is crucial for appropriate patient management and to prevent unnecessary transfusions.
Observation:
- Three unrelated African-American patients with FVII deficiency were studied.
- Clinical laboratory values indicated low FVII coagulant activity.
- Testing utilized both rabbit brain and human thromboplastin assays.
Findings:
- A specific G to A nucleotide change was identified as the cause of FVII deficiency.
- This mutation results in an arginine to glutamine substitution at amino acid position 304 of Factor VII.
- The identified mutation led to reduced FVII coagulant activity when using rabbit brain thromboplastin, but not human thromboplastin.
Implications:
- This genetic finding provides a molecular explanation for FVII deficiency in African Americans.
- Understanding the specific mutation aids hematology specialists in interpreting patient laboratory results.
- The findings can help prevent unnecessary transfusions by clarifying the cause of abnormal FVII activity.