The Leeds Teaching Hospitals NHS Trust

Frequently asked questions

What is a UKAS accredited lab?

Please see UKAS website for more information.

Transportation requirements for all specimens?

See Taking and Sending Samples.

How long will it take to get a result?
See Turnaround Times.

What should be done with a sample taken late in the day?

Samples can be stored in a fridge overnight at 4C, but on no account should they be frozen. If in doubt contact  the laboratory.

What on-call cover is provided?

The laboratory does not provide an on-call service. Please contact the relevant Head of Section for advice.

What bank-holiday cover is provided?

A skeleton staff operates the laboratory on bank-holidays, to perform essential tasks. If results are required please contact the laboratory  to discuss.

Why do I have to provide the patient’s address/postcode?

This allows easier positive patient identification and is also necessary for cross charging purposes. Provision of these details on the request card saves us all a lot of time later on.

How much blood is required for cytogenetic chromosome analysis?

Adults 5ml
Children 2-5ml
Infants 1-2ml

How much blood is required for a breakage syndrome?

Fanconi Anaemia - Minimum of 2ml

Blooms Syndrome - Minimum of 1ml

What number do I need to ring to get a DNA result?

0113 206 5205 (x65205 internally).

What information about a patients genotype will karyotyping provide?

Realistically, none in regards to specific genes although gain or loss of material detectable by G banding will have genotypic implications.

What is the smallest size of genetic change that G-banding can detect?

Approximately four to six megabases depending on banding resolution.

What additional tests are available?

Material from amniotic fluid samples, chorionic villus samples and tissue samples is frequently cultured by the laboratory with a view to sending the cultured material for further genetic, biochemical or immunological testing at the request of an appropriate specialist.

What packaging is required for samples?

Samples can be sent by first class post, courier, taxi or hospital transport. Whichever method is used, samples should be packaged correctly. They should be sent in jiffy bags with a request card slotted separately from the specimen. The bags should then be placed inside an absorbent container with absorbent packaging such as cotton wool. Specimens must be labelled as biological hazards. For more information please see here.

How should urgent samples be sent to the laboratory?

It depends on where the sample is from, but remains the responsibility of the sender. Samples can be sent by first class post, courier, taxi or hospital transport. Whichever method is used, samples should be packaged correctly. Jiffy or padded envelopes should not be used as they do not provide adequate protection. For more information please see here.

What do I do with a tissue sample when I have no tissue transport medium?

Sterile saline can be used, and transport medium may be available from your microbiology department.

What tube should I use to collect blood in?

See Taking and Sending Samples.

Help! I don’t have a request card.

Referrals cards can be accessed here.

Can I send paraffin sections?

With prior arrangement with the laboratory.

I am a patient, can I have my result?

The laboratory does not give results to patients over the telephone. Contact your Consultant or GP who will discuss your results with you. Printed copies of results will only be provided in response to written enquiries after discussion with the trusts Caldicott Guardian.

The patient has just had a transfusion, when can I take blood for cytogenetic analysis?

Transfusion is usually with leukocyte depleted blood, so there is generally no need to wait.

Is old transport medium ok for marrows, tissues and tumours?

Transport medium will keep for one month (3 months for marrow transport medium) if refrigerated and should be discarded after that date. The cytogenetics lab can supply replacement stocks of transport medium at short notice if requested.

Can the laboratory send material to Porton Down?

The laboratory will package samples to send to Porton Down, however it is the responsibility of the referrer to complete all the necessary forms and arrange and pay for transport other than first class mail.

What are the criteria for sub-telomeric screening?

This service is only available for samples referred by Clinical Geneticists.

How long do the laboratory store samples for?

Bloods: Until the final report is issued
FISH: Indefinitely as fixed material.

Can we FISH frozen sections?

Yes – sections need to arrive on dry ice after which they are gradually thawed to room temperature. FISH can then be performed either as a touch preparation or on disaggregated cells.

Can H&E stained slides be FISHed?

Yes, provided the slide has been destained.

Can we send a sample that has been in our fridge for 5 days?

Yes, but we cannot guarantee a result.

What happens to confidential data?

The Genetics Laboratory adheres to the Leeds Teaching Hospitals policy for patient information and data. Please see for further details.

Can I make a complaint about the laboratory?

Yes, you can complain through this link.