Solid tissues

Sample requirements

Skin, placental material or products of conception

Samples should be referred in sterile isotonic saline in a sterile universal or other sealed sterile container. Fresh samples should ideally be sent to the Cytogenetics Department on the same day. Where a delay is inevitable (such as over weekends) please store the sample in a refrigerator. Please note that we cannot process samples that have been exposed to formalin.

Please avoid using large containers or sending large quantities of liquid. Please ensure all containers can be securely sealed (preferably screw caps) and are appropriately packaged (see packaging guide).

Please ensure that the referral form is separated from the vessel by a waterproof layer in case of leakage during transport.

 

Effusion or ascitic fluid

Samples should be referred in a sterile universal or other sealed sterile container.

 

Buccal smears

Samples should be applied to poly-l-lysine coated slides, please contact us to discuss your requirements. These samples can only be processed for targeted FISH.

 

Acceptance Criteria

In order to target limited resources, for this group of referrals the Cytogenetics Department operates an acceptance policy, please see below. For referrals which do not fulfil these criteria please contact the laboratory to discuss the test you require.

                                 

Referral categories:

  • Patients with recurrent pregnancy loss (2 or more previous) unless the patient is over 35
  • Fetal abnormality
  • Abnormality on scan
  • IUFD
  • Stillbirth
  • Family known to carry a chromosome abnormality
  • Fibroblast cultures requested (more information below)
  • Specific clinical request
  • Confirmation of an abnormal prenatal test
  • Investigation of suspected inter-tissue mosaicism (can also be referred from live-born patients)
  • Buccal smears (targeted FISH only) available for severely needle phobic patients

 

Tests

Microarray

Fetal skins, placenta and products of conception material will usually be processed by microarray for identification of genetic imbalance over 1Mb in size, unless otherwise indicated. In addition this test will identify triploidy and true molar pregnancies. If mosaicism is indicated in the referral, cultures may be established as well as DNA extraction for microarray testing. Please indicate clearly on the referral card if mosaicism is suspected.

 

Targeted FISH

For other samples, we offer a targeted FISH test if appropriate.

 

Fibroblasts

Skin samples can be sent to the Cytogenetics Department to establish fibroblast cultures which can then be forwarded for biochemical assays, molecular tests or for DNA extraction/storage. Samples for these referrals should be of full thickness where possible. If appropriate, the skin sample should be accompanied with a letter to the appropriate testing centre where the cultures are to be forwarded. The letter should also include the test required and the name and address of the requesting clinician.

 

Reporting times

Solid tissues are usually reported within 42 days. If you have a specific request for a result urgently, please contact the laboratory.

Please see our reporting timetable.

 

Limitations

Please see our solid tissue limitations of testing.

 

Storage and further testing

Where samples have been cultured for karyotype analysis, material is available for 14 days after reporting for most referrals. This is extended to 28 days for fibroblast cultures for onward referral. Fixed material (if the sample has been cultured for karyotype analysis) is stored for at least 10 years for cases with an abnormal karyotype. Fixed material from cases with a normal karyotype are stored for 3 months from the date of receipt before discarding. DNA from microarray is stored indefinitely. 

Page last updated 14/08/2018. Please note that if printed, the information is only valid on the day of printing.