Division of Molecular Genetics
Chief Molecular Geneticist: Prof David Barton
Enzyme, electrophoresis, fluorescence and autoradiographic technologies are applied to detect the changes in DNA structure and sequence that underlie specific genetic disorders.
As the human genome (the full complement of DNA) is so large and complex, each test can only examine a tiny portion of a patient’s DNA (typically one billionth), so the tests applied are entirely specific for a particular disorder.
The table below itemises the disorders tested for in the Division of Molecular Genetics at present.
We also maintain a register of hundreds of diseases for which tests are available abroad, and for which we provide a referral service, which includes DNA preparation. Turnaround times for DNA preparation + despatch are currently approximately 4 weeks for routine referrals , and 1 week for urgent referrals (e.g. prenatals, predictive tests, neonates). Please contact us at firstname.lastname@example.org or 01-409 6733 for queries regarding molecular genetic tests not listed below.
The Division of Cytogenetics accepts requests for microarray testing (array CGH) from hospitals with which it has a service agreement (currently only Our Lady’s Children’s Hospital, Crumlin and the Children’s University Hospital, Temple St.). Microarray testing requests from other hospitals cannot be accepted at present. Please direct all enquiries to the Chief Scientist in Cytogenetics via the Contacts page.
The Centre does not carry out paternity testing for non-medical purposes. Links to commercial paternity testing services are provided.
Turnaround times shown are for routine diagnostic testing. Urgent cases are prioritized and reported as soon as is reasonably possible; more complex testing may take considerably longer.
If the test you want is not listed, please contact the Molecular Genetics laboratory.
|Disorder||Synonyms||Turnaround Time (indicative for routine tests)|
|Angelman Syndrome (MSWord)||AS||6 weeks|
|Beckwith-Wiedemann Syndrome||Wiedemann-Beckwith syndrome, BWS||Discontinued. Please refer patient to Clinical Genetics.|
|Familial Breast Cancer (PDF)||BRCA||See further details within BRCA Service Description|
|Cystic Fibrosis (PDF)||CF, Also includes testing for Male Infertility as a result of Congenital Bilateral Absence of Vas Deferens, CBAVD||6 - 8 weeks|
|Duchenne Muscular Dystrophy (MSWord)||DMD, the milder form is Becker Muscular Dystrophy (BMD)||6 weeks. See also Note #2 below.|
|Early-Onset Torsion Dystonia (PDF)||DYT1, Dystonia musculorum deformans 1||Up to 6 months|
|Fragile X Syndrome (PDF)||FRAX, Martin-Bell Syndrome. Also includes testing for Premature Ovarian Failure (POF) & Fragile X-Associated Tremor/Ataxia Syndrome (FXTAS).||Up to 6 months|
|Friedreich Ataxia (PDF)||FRDA, FA||12 weeks|
|Hereditary non-Polyposis Colon Cancers including Microsatellite Instability, MSI, analysis (PDF)||HNPCC, Lynch Syndromes I & II||See further details within HNPCC Service Description|
|Huntington Disease (PDF)||HD, Huntington Chorea||8 - 10 weeks|
|Osteogenesis Imperfecta Type VIII (MSWord)||OI Type VIII||Enquire|
|Prader Willi Syndrome (MSWord)||PWS||6 weeks|
|Progressive familial intrahepatic cholestasis type 1 (PDF)||Byler disease||Enquire|
|Russell Silver Syndrome (PDF)||RSS, maternal uniparental disomy of chromosome 7, mUPD7||12 weeks|
|Sickle Cell Anaemia (Prenatal testing only)||HbSS||Please contact Clinical Genetics urgently, & in advance, with enquiries regarding Sickle Cell Anaemia prenatal testing.|
|Spinal Muscular Atrophy (MSWord)||(SMA Types I, II, III, and IV), Werdnig-Hoffman disease, Kugelberg-Welander||6 weeks. See also Note #2 below re temporary external testing arragements, during which turnaround time for urgent neonatal referrals will be up to 3 weeks.|
|Uniparental disomy (PDF)||UPD (see also Russell Silver Syndrome)||3 months|
Information as per DOC1416, revision 6.
Please note that, for a limited period from August 2011 to the 2nd quarter of 2012, all DMD & SMA testing will be provided for via external referral laboratories. This is due to staffing shortages. During this period, SMA turnaround time for urgent neonatal testing will be 2-3 weeks.
Requests for test results
Please contact the laboratory if you have not received a report within a week of your patient being due back in clinic.
Please note it is our policy not to issue verbal results.
Request for copies of reports on the day that your patient is in clinic cannot normally be accommodated. We usually require 24 hours notice in which to fax a copy of a report.
Please check with your Pathology Laboratory for copies of reports before contacting the Division of Molecular Genetics as all reports are copied to the appropriate Pathology Laboratory at the time of issue.
Enquiries from Patients: please note that the laboratory cannot deal with direct enquiries from patients. For general enquiries, where a molecular genetic test has not yet been requested, please contact Clinical Genetics.
Turnaround times vary according to test complexity and sample numbers received.
Indicative times for routine testing are presented in the table above.
For further details re reporting times for each category of test offered, please refer to the Service Description for the relevant disorder, via the hyperlinks in the table.
These reporting times are much longer than they should be because the resources available to carry out this work have not kept pace with the rapid growth in sample numbers and test complexity.
The Molecular Genetics laboratory is accredited by CPA(UK) Ltd to the CPA standards incorporating ISO 15189.
As part of its commitment to total quality, the Molecular Genetics Laboratory participates in the external quality assurance schemes run by the United Kingdom National External Quality Assessment Service, UKNEQAS, and by the European Molecular Genetics Quality Network, EMQN.
National Centre for Medical Genetics staff are on the steering committees of both these schemes. Prof. David Barton chairs the Management Board of EMQN.
Copies of the results of these external quality assessments are available on request.
Samples and information required
- Generally 5-10ml venous blood in an EDTA tube is required, except where otherwise indicated.
- If your patient has recently been transfused or has ever had a bone marrow transplant, please read the “Transfusions and Transplants information sheet”.
- Samples for molecular genetic analysis may be refrigerated.
- Other sample types by arrangement only. Please note that prior notification is required for all prenatal referrals to the Division of Molecular Genetics. Notification should occur prior to a prenatal specimen being taken, and prenatal testing should be arranged through a Clinical Genetics department if possible.
- Summary clinical and family history information must accompany every sample, including (when available) names, dates of birth, clinical details and copies of genetic test results from the relevant family member(s).
- Use local request forms or obtain forms from the centre. Forms to help you give us the information we need are available directly from the laboratory, or can be downloaded from the ‘downloads’ area to the right of the page.
Sample ID policy
As part of a continuing process of quality improvement, the NCMG has formalized 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 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 Scientist, Prof David Barton.