Sample Types


Chromosome (Cytogenetic) Analysis


Prenatal samples

Amniotic fluid – Send 10-20ml in a sterile, leak-proof, plain (no anticoagulant) plastic container. Samples for microarray analysis must be accompanied by a maternal blood sample (5ml EDTA).  Do not freeze or expose to heat. Must arrive in lab within 24 hours.

Chorionic villi – The minimum size requirements for the specimen are dependent on the reason for referral, usually 10-30mg in a sterile transport medium; contact the laboratory on 0161 276 6553 for more details. CVS samples should be received on the same day they are taken and preferably no later than 4.00pm. For samples referred for microarray analysis or a parental balanced rearrangement (ie, inversion or translocation) a maternal blood sample (5ml in EDTA) is required. Do not freeze or expose to heat. Must arrive in lab within 24 hours.

Fetal blood – Send 1ml in a 2ml paediatric lithium heparin tube and mix well to avoid clotting. Please clearly mark the sample as “fetal blood”.

Postnatal samples
Do not freeze or expose to heat. Can be stored overnight at 4°C if required.

Venous blood – samples for karyotyping, use lithium heparin tube only. We require at least 5ml for adults and children, at least 1ml for neonates. Send within 48 hrs of venepuncture and mix well to avoid clotting.

Samples for microarray testing (developmental delay, congenital abnormalities etc) please follow the guidelines for Gene(DNA) Analysis below

Chromosome breakage tests are initiated on a Tuesday or Friday morning ONLY. Please take this into consideration when sending blood samples to the laboratory for testing. Testing for Fanconi Anaemia requires a minimum of 2ml blood in lithium heparin.

Solid tissue – Do not expose to formalin. Send in a leak-proof, dry, sterile, plastic container, or sterile saline if stored overnight. The container should be wrapped with absorbent material and placed in a sealable polythene sample bag. The most appropriate tissue types to send us are:

  • A full depth skin sample (0.5cm3).
  • A sample of cord (2-3cm in length; please do not include a cord clip)
  • A cord or cardiac blood sample (at least 0.5ml collected into a 1-2ml lithium heparin paediatric tube).


Please read our Solid Tissue Sample Requirements and Referral Criteria for further information.



Skin Biopsy for fibroblast cell culture – Skin biopsies should taken into tissue transport medium available from the GDL by contacting the Duty Scientist (0161 276 6553) prior to the procedure.  Samples may also be collected in sterile saline.  Sample should be sent to the laboratory as soon as possible following sampling, to arrive at the laboratory between 9am and 5pm Monday to Friday, and may be refrigerated overnight if necessary.


Gene (DNA) Analysis

Please refer to individual test pages for more specific requirements. Alternatively please contact the laboratory for further details. For general samples please see below:

Blood samples
Use EDTA tube only. We require at least 4ml for adults and children, at least 1ml for neonates. Store at 4°C and send by first-class post.

Mouthwash samples
Use Oragene container only. Advice on how to obtain these is available from the laboratory office.
Other samples
By prior arrangement only. Please contact the laboratory for more details.



The Willink Metabolic Unit — Biochemical Genetics Analysis

Due to the wide range of tests carried out for biochemical genetic indications, it is not possible to list the full sample requirements. Please see the relevant service profile for detailed sample requirement. However, for guidance, the following sample types are used:

  • Blood – use EDTA or lithium heparin tube, depending on test.
  • Plasma
  • Urine
  • Liver
  • Amniotic fluid
  • Chorionic villi
  • Cerebrospinal fluid
  • Cultured skin fibroblasts
  • Cultured amniotic fluid cells
  • Cultured chorionic villi



Specialist Cell Culture Samples

Blood samples
Peripheral blood samples for lymphocyte separation or EBV transformation to establish a cell line require 10-20ml blood (adults) or 2-10ml (children) collected in an Acid Citrate Dextrose (ACD) or Sodium Heparin tube.  EDTA collection tubes may be used if ACD is not available.

  • Peripheral blood samples for RNA analysis require 10-20ml blood (adults) or 2-10ml (children) collected in an EDTA tube.
  • All other sample types are by prior arrangement only. Please contact the laboratory for information and advice before sending.