Prenatal Diagnosis for Carriers of Balanced Chromosome Rearrangements
Description:
Following exclusion of trisomies 13, 18 and 21, samples are tested using fluorescence in-situ hybridization (FISH) probes specific for the familial rearrangement. This strategy will detect/exclude the major trisomy syndromes and unbalanced products of the parental balanced chromosome rearrangement.
Clinical details:
For some carriers of balanced chromosome rearrangements there is an increased risk of chromosome imbalance in their fetus due to the random assortment of the parental derivative chromosomes at meiosis. Our testing strategy enables rapid detection/exclusion of unbalanced products of the rearrangement.
Synonyms or keywords:
Rapid aneuploidy detection, Balanced chromosome rearrangements, Carrier testing, FISH, Prenatal testing, CVS, AF.
Department:
Location:
Sample type and Volume required:
Amniotic fluid in a dry sterile container (10 - 20ml), CVS (20mg please discuss with the laboratory)
Call in advance:
Please notify the laboratory before sending prenatal samples
Turnaround time:
1 - 3 working days
Special sample instructions:
Request form available at: https://southeastgenomics.nhs.uk/wp-content/uploads/2023/08/SE-GLH-Non-WGS-Genetic-Test-Request-Form-August-2023-v1.5.pdf
- R298 Possible structural or mosaic chromosomal abnormality - FISH
Include the relevant R code (above) on the referral form; for further details and the eligibility criteria for testing please see https://www.england.nhs.uk/publication/national-genomic-test-directories/
Storage and transport:
All prenatal samples must arrive in the laboratory on the day of sampling, preferably before 3pm.
Cost:
On application
Time limit for extra tests:
Do not spin down or freeze samples before sending.
Contacts:
For clinical advice or interpretation of results, please contact the laboratory in the first instance.
Laboratory:
Last updated: 26/10/2023
