Cytogenetics Division
Chief Cytogeneticist: David Betts
Since 2008 we have been forced to restrict the Cytogenetics services we offer. The situation is being constantly monitored (please see Latest News on home page).
Currently we will only be accepting peripheral blood samples from the following referrals:
- Children (<5 yr old) for karyotype analysis
- Microdeletion syndromes for FISH-only analysis
- On-going family studies
Restrictions are still in operation for the ‘Product of Conception’ service and we only accept the following tissue samples:
- Tissue from live borns with documented abnormal phenotypic features
Analysis of pre-natal samples remains unaffected.
Please see the Cytogenetics User manual for further information.
If you have any enquiries, please contact the Cytogenetics Laboratory.
The Cytogenetics Laboratory at the National Centre for Medical Genetics was established in January 1995 to provide a general cytogenetics service to the Irish population.
A wide variety of tests are offered on metaphase chromosomes derived from peripheral blood lymphocytes, bone marrow cells, skin and placental fibroblasts, and amniocytes.
The laboratory offers high resolution G band chromosome analyses and a comprehensive molecular cytogenetics service involving fluorescence in situ hybridization (FISH) for microdeletion syndromes (e.g. Miller-Dieker, Williams, DiGeorge, Smith Magenis, Cri-du-Chat, Wolf Hirschhorn, Kallman and Retinoblastoma).
A large number of other FISH probes, including oncology probes, are available upon request. The Laboratory operates in close collaboration with the Clinical Genetics Unit and the Molecular Genetics laboratory at the National Centre.
Services offered
The Cytogenetic Lab offers analyses on:
- Blood (2ml in lithium heparin is required).
- Skin (in sterile transport media).
- Bone marrow and peripheral blood for oncology studies (0.5 - 1ml in transport medium with heparin).
- Amniotic Fluid (10 ml of amniotic fluid is required).
- Chorionic villi (please contact lab before taking sample).
Samples for cytogenetic analysis should not be refrigerated. All samples must be accompanied by a referral form and packaged according to UN guidelines. All samples must be accompanied by a referral form and packaged according to UN guidelines.
If your patient has recently been transfused or has ever had a bone marrow transplant, please read the “Transfusions and Transplants information sheet”.
Microarray Testing
While we are working on developing microarray testing for copy-number variations at the NCMG, we are sending all such requests abroad for testing. Requests are accepted for testing only from patients who exhibit developmental delay and/or dysmorphism and/or congenital abnormalities. 3-5ml blood in an EDTA tube should be sent to the Molecular Genetics Laboratory with all requests for microarray testing. Invoices for tests sent abroad will be directed to the referring institution.
Reporting Times
| Sample Type | Average report time (days) | Median report time (days) | % within guidelines |
|---|---|---|---|
| Amniotic Fliud (AF) | 14 | 14 | 67% within 14 days |
| Chorionic Villus Sample (CVS) | 15.6 | 15 | 30% within 14 days |
| Urgent Peripheral Blood (infants <6weeks old) | 8.8 | 8 | 33% within 7 days |
| Routine Peripheral Blood | 31.2 | 26 | 61.8% within 28 days |
| Solid Tissue | 29 | 28 | 50% within 28 days |
| Diagnostic leukaemia (ALL, AML, CML) | 9.7 | 9.5 | 100% within 14 days, 20% within 7 days |
| Routine haematological samples | 23 | 18 | 52% within 21 days, 60% within 28 days |
New sample ID policy
As part of a continuing process of quality improvement, the NCMG is formalizing its sample identification policy, to ensure that all samples accepted for testing are identifiable to a unique individual. A summary of the policy is available in PDF format. Please note that from October 2nd, 2006 samples not complying with this policy will not be accepted for testing.
Any questions you may have about the policy may be addressed to the Chief Cytogeneticist, David Betts.
Quality Assurance
The laboratory participates in the UK NEQAS quality assessment scheme in clinical cytogenetics.