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  Amplification techniques, such as polymerase chain reaction (PCR), etc., now allow minute samples to be   tested, the larger the sample, the better the chance of a suc c essful DNA test. Post-mortem material is inferior to live blood and tissue for DNA fingerprinting if any significant post-mortem change has proceeded enough to break down nuclear chro m atin. Plain blood samples should be taken, however,   though leucocytes may have already disintegrated. Some 5 ml of blood is taken into an EDTA tube, which extracts metallic ions and not only prevents clotting, but inhibits enzymes in blood or micro-organisms, which may break down DNA during storage. The best material is said to be - muscle or the spleen and, if decomposition is advancing, the bone marrow is recommended. At least 0.5 g of tissue should be cut from the parenchyma of an organ and placed in a small plastic tube with no fixative or preservative.   This should be frozen at -20°C if there is likely to be...

  The identity of the dead is an essential part of post-mortem examination, for various reasons. These include: -           the ethical and humanitarian need to know which individual has died, especially for the information of surviving relatives; -           to establish the fact of death in respect of that individual, for official, statistical and legal purposes; -           to record the identity for administrative and ceremonial purposes in respect of burial or cremation; -           to discharge legal claims and obligations in relation to property, estate and debts; -           to prove claims for life insurance contracts, survivor's pensions, and other financial matters; -           to allow leg...

  Most of the discussion concerning the definitions of death belongs to the field of legal medicine and even that of ethics, rather than forensic pathology. Notwithstanding this, a quick review of this complex problem is appropriate here, as when we come to describe the various post-mortem phenomena, some appreciation is necessary of the zero point from which such changes are timed. It is conventional to describe two types of death:      somatic death, in which the person irreversibly loses its sentient personality, being unconscious, unable to be aware of (or to communicate with) its environment, and unable to appreciate any sensory stimuli or to initiate any volunrary movement. Reflex nervous activity may, however, persist, and circulatory and respiratory functions continue either spontaneously or with artificial support so that the tissues and cells of the body, other than those already damaged in the central nervous system, are alive and functioning. ...