Cytogenetics Service
Comprehensive constitutional chromosome analysis is offered for
a range of referrals (postnatal and prenatal) using high density
oligonucleotide microarrays, G-banding karyotyping and fluorescence
in situ hybridization (FISH). Other DNA based cytogenetics
tests employed by the laboratories include quantitative
fluorescence polymerase chain reaction (QF-PCR) and multiplex
ligation probe amplification (MLPA).
Samples can be forwarded to other laboratories for tests not
available in-house e.g. prenatal samples for rapid QF-PCR
testing, or prenatal and parental bloods for haemaglobinopathy
testing. Cultured cells can be forwarded to specified locations as
requested - please contact the lab to arrange this.
Cytogenetic testing:
News
June 2022
Test backlogs
Non-urgent requests for the following tests are currently not
being reported within the NHSE guidance turnaround time target of
42 days:
Chromosomal microarray (current TAT approximately 4 months)
Karyotyping (current TAT approximately 8 weeks)
We are actively monitoring and working on these backlogs to
improve the situation for our users. Please contact the laboratory
for any clinically urgent cases as these may be able to be
prioritised and reported within the target turnaround time.
Please contact the laboratory if you have any concerns or
feedback about a specific case.
Downloadable documents:
Sending samples to the cytogenetics laboratory
It is the responsibility of the patient's clinician to
request a laboratory service/test and to ensure that all samples
are correctly labelled and request forms completed to a minimum
standard.
Consent is not required for DNA storage. It
is the responsibility of the clinician to obtain consent before
requesting a genetic test.
Blood Samples
5ml venous blood in plastic EDTA bottles (>1ml from neonates)
for DNA-based tests (e.g. microarray).
2ml venous blood in plastic lithium heparin bottles (at least
1ml from neonates).
Sample must be labelled with:
- Patient's full name (surname/family name and given/individual
name)
- Date of birth and unique hospital/NHS number
- It is desirable to have the date and time sample was taken
and/or location as well the name of the person who took the
sample
Prenatal Samples
Tissue type and date of biopsy should be clearly documented on
the referral information together with the name of the person who
took the sample.
In the case of twins, special attention must be given to the
identity of each sample.
Minimum criteria:
- Patient's full name (surname/family name and given/individual
name)
- Date of birth and/or unique hospital/NHS number
DNA Samples
The Association for Clinical Genomic Science
(ACGS) guidelines recommend at least two pieces of identifying
information on every sample tube.
- Patient's full name (surname/family name and given/individual
name)
- Date of birth and/or unique hospital/NHS number
- Other information provided with referrals should include a
pedigree, where appropriate, with the full names of known
individuals and correct family identifiers
- If results are received e.g. allele numbers, a full explanation
of the terminology should be included
Samples which do not meet
these criteria may be rejected.