Types of human tissue collections

19.7 Human tissue collections are established and maintained in three main contexts: by pathology laboratories in conducting medical testing, by health authorities in the conduct of newborn screening programs, and by tissue banks that hold stores of tissue for transplantation and therapeutic use. Each type of human tissue collection is described below.

Archived pathology samples

19.8 Pathology laboratories receive samples of blood, body fluids and tissue from doctors and hospitals for testing. Such tissue may have been removed during surgery or via a medical examination. Pathologists examine test results to aid in determining the cause of a condition and how it should be treated.[3]

19.9 The pathologist’s findings and analysis are reported to the doctor who ordered the tests. However, the laboratory will retain any remaining portion of the sample once testing has been completed. These samples are archived and may be kept for some time. Samples are retained to fulfil laboratory accreditation requirements[4] or to meet laboratory standards. There may also be legal reasons for keeping samples, and a laboratory may wish to be able to re-test samples to confirm results at a later stage. Collections of pathology samples are, therefore, comprised of residual tissue taken primarily for therapeutic and diagnostic purposes. Although samples are generally coded when a pathology laboratory receives them, the laboratory retains the means to unite a sample with its identifying information.

19.10 Samples are stored in a variety of forms. Some are fresh-frozen and kept refrigerated. Others, like sections of tissue, are embedded in paraffin to enable slides to be made from cut sections. These blocks of tissue can be stored for a long time without significant deterioration.

19.11 Samples are sometimes disposed of once they have no further use. Usually this involves steam-heating samples to melt containers and destroy the contents. The heat at which they are melted is sufficient to denature any DNA contained in samples, while the process prevents separation of individual containers. Once cooled, destroyed samples are generally deep-buried.

Newborn screening cards

19.12 In hospitals around Australia, blood has been taken from newborns, and the sample identified and stored, for the last 30 years. Between two and five days after birth, virtually all children are screened for a variety of conditions. A small sample of blood is taken and placed on a piece of blotting paper. The child’s name, date of birth, hospital of birth and birth weight, and the mother’s name and date of birth, are also recorded on the card.[5]

19.13 These cards are referred to in this Report as ‘newborn screening cards’. The cards are also commonly known as ‘Guthrie cards’, a name derived from the scientific test once used to detect phenylketonuria. They are now more correctly referred to as newborn screening cards because the Guthrie test is no longer universally used and newborn screening also includes other tests.

19.14 Samples are obtained with verbal parental consent. Parents are supplied with an information leaflet detailing the screening program, the tests that are performed and (in some cases) the fact that cards are stored and may be used or disclosed for other purposes. In South Australia and New South Wales parents are usually also notified that the cards, once de-identified, might be used in approved research.[6] Screening program staff are generally required to discuss the contents of this leaflet with parents to ensure they have fully understood the information provided before giving consent. However, as discussed below and in Chapter 24, doubts have been expressed about whether this constitutes proper consent.

19.15 Cards are stored for different periods in each State and Territory, ranging from two years in Western Australia to much longer periods in most other jurisdictions. Cards are retained for quality assurance and laboratory auditing purposes and for retrospective diagnosis. Retrospective diagnosis can directly assist some children.[7] In addition, where a child has died, stored cards can be used to confirm the mutation for a genetic condition, enabling carrier testing of family members.[8] Cards are also stored to help testing services to devise and trial new screening tests.

19.16 In 1999, the Senate Legal and Constitutional Legislation Committee referred to newborn screening card collections as ‘inadvertent DNA sample banks’, noting that identified blood samples containing genetic material from almost all people under the age of 28 are currently stored in most States and Territories.[9]

Tissue banks

19.17 A variety of tissue banks have been established in Australia to hold donor tissues for transplantation and therapeutic uses. Unlike the human genetic research databases discussed in Chapter 18 (which are also sometimes referred to as tissue banks), these banks have not been created for research purposes. They may, however, house collections of human tissue that might be used for research or other secondary purposes.

19.18 For example, the Perth Bone and Tissue Bank receives donations of bone for transplantation and therapeutic use. Bones are received from living individuals (who, for example, donate bone removed during hip replacement surgery) and from deceased individuals. Sections of bone obtained from failed grafts are sometimes used in research projects by the Bone Bank.[10] The Australian Red Cross Blood Service collects blood donations for whole-blood transfusions and the manufacture of therapeutic products. On rare occasions, the Australian Red Cross Ethics Committee considers requests for access to blood samples for research purposes.[11]

19.19 Human genetic samples are also banked commercially in the form of cord blood. Firms such as Cryosite, based in Sydney, store blood taken from the umbilical cords of newborn infants. Parents pay for storage so that they will be able to access the blood, which can be used in the treatment of some diseases, if their child becomes ill.[12]

19.20 Some genetic registers also maintain banks of genetic samples. These may be used for presymptomatic diagnosis and carrier detection. Where a disorder has been identified but a reliable molecular test has not yet been developed, samples may be banked for testing once a reliable test becomes available.

[3] For example, a general practitioner who suspects a patient has anaemia may take a blood sample and send it to a pathology laboratory for analysis. The sample will be tested for haemoglobin levels and examined under a microscope to look for signs of iron deficiency like abnormally small cell size.

[4] See Ch 11.

[5] A newborn screening card is reproduced at the end of Ch 24.

[6] NSW Health Department, Test to Protect Your Baby (2000), NSW Health Department, Sydney; South Australian Neonatal Screening Centre, Screening Tests for Your New Baby (2002), Adelaide.

[7] For example, in relation to testing for congenital cytomegalovirus (CMV) infection: Genetic Health Services Victoria, Submission G211, 28 November 2002.

[8] For example, in relation to testing for Duchenne muscular dystropy: Ibid.

[9] Senate Legal and Constitutional Legislation Committee, Provisions of the Genetic Privacy and Non-discrimination Bill 1998, The Parliament of Australia, <www.aph.gov.au/senate/committee/legcon_ctte/
genetic/index.htm>, 21 August 2002, 3.

[10] A Cowie (Perth Bone and Tissue Bank), Correspondence, 2 July 2002. Specific consent for research use is always sought from donors.

[11] Australian Red Cross Ethics Committee, Submission G292, 6 January 2003. Ethics approval to date has always required individual consent, frequently restricted access to de-identified or coded samples only, and has never involved a waiver of consent.

[12] D Teutsch, ‘Born to be Insured’, Sun Herald (Sydney), 30 June 2002, 27.