Clinical information
Diagnostic Utility:
Determining the presence of the mutation causing the familial pathology in the fetus from samples of chorionic villi (CV) or amniotic fluid (AF). Studying the mutation in the fetus will allow for genetic counselling.
Analysis of the region/s of the gene/s where the mutation causing the familial pathology is located using different techniques that may vary depending on the type of mutation. Prenatal study of congenital coagulopathies can be requested in cases where a pregnant woman known or suspected to be a carrier of haemophilia, or in the case of any other congenital coagulopathy where it may be indicated.
Method:
Prenatal diagnosis is carried out in parallel with the fetal DNA sample obtained from CV or AF and the mother's DNA (provided that this sample is available to confirm the familial mutation).
Conjoint and systematic analysis of 15 DNA microsatellites and a sex marker. Sex determination will be confirmed by PCR.
Genetic analysis of the specific region of the gene where the familial mutation is identified, both in the maternal and fetal samples. Depending on the type of mutation, sequencing by Sanger, LR-PCR or MLPA will be performed.
Reference Values
Not applicable
Diagnostic Algorithm:
Confirmation of the maternal-fetal relationship through STRs, thereby ruling out sample errors and fetal DNA contamination with maternal DNA.
Identification of the sample's sex and the presence/absence of the familial mutation.
Turnaround Time:
5 working days.
Specimen information
Sample: Chorionic Villi, Amniotic Fluid.
Tube: Falcon tube 5-10 ml.
Minimum essential volume: In the case of Amniotic Fluid 2ml.
Stability:
- At room temperature: 10 days.
- In refrigeration: 30 days.
Transport instructions: Preferably at room temperature.
Reason for rejection: Sample contaminated with maternal blood and/or incorrectly identified.
Administrative information
BST Code: LRD2235
Test Description: Prenatal study of congenital coagulopathies.
Synonyms: Prenatal diagnosis.
Section: Congenital Coagulopathies
BST Rate: Check the updated rates here.
The molecular study request form must indicate the name of the pregnant woman, the family reference, and the relationship between them. All necessary genealogical information must be provided to correctly carry out the study, especially for autosomal pathologies. In addition, the available phenotypic and molecular data must be completed. The comments section must clearly indicate that it is a prenatal study.
Profiles:
N/A.
References
- DNA Sequencing by Capillary Electrophoresis. Applied Biosystems Chemistry Guide. Second Edition.
- Protocol de cribratge prenatal d'anomalies congènites a Catalunya. 2018, Generalitat de Catalunya. Departament de Salut. Agència de Salut Pública de Catalunya