(b) Plain X-rays: Any bone showing signs of damage, for example by gunshots, must be X-rayed for metallic objects invisible to the naked eye. Chemical tests can be used to identify the presence of lead or copper, e.g. from projectiles. X-rays are also very useful for evaluating bone pathology X-rays should be taken before any cleaning of the remains occurs. This is particularly important with partially decomposed remains, where commingling might not be detected upon exhumation (c) Cleaning/sampling: If their condition allows, all the bones and teeth should be washed with simple running water and no other product. A trap must be in place to capture any material that might be dislodged by the water. In a case of severely decomposed skeletal remains, however, washing can be detrimental. A brush with soft bristles, such as a toothbrush, may be used to remove dirt, special care being taken with worn bones, such as the epiphyses of the long bones and the faces of the pubic symphysis. Teeth not permanently attached to the alveolar bone should be removed and washed separately, to prevent their loss In cases where the remains are not completely reduced to bone, and soft tissue is still attached, a non-chemical method should be used for cleaning, under strict control. Such a process shall only be undertaken once the forensic pathologist has evaluated and properly documented the remains and the necessary samples have been collected. Once the remains have been washed, they should be allowed to dry, preferably away from light and without exposing the bones to the sun. A fan can be used to speed up the process (d) Sampling: The main reason for taking samples when analysing skeletal remains is to perform a genetic analysis that could help in identification. This procedure must be coordinated, as sampling methods vary according to the requirements of the DNA laboratory. Depending on the condition of the skeleton and the number of individuals represented, the anthropologist has to decide how many samples to take. This decision is more complicated in commingled cases, and must take into account the wider strategy on how to analyse such complex cases. Usually, two or three healthy teeth and a sufficient quantity of a long bone, such as a femur or tibia, are enough for the sampling of a complete individual skeleton. (It is preferable for such sampling to take place before the teeth and bones are cleaned, to avoid new contamination) 50 The Minnesota Protocol on the Investigation of Potentially Unlawful Death (2016) (e) Reconstruction: The bones presenting peri- or post-mortem trauma may have to be reconstructed. Special glue, which allows the fragments to be separated without damage in the event of an error, should be used. 4. Establishing a biological profile of the remains 282. Once the remains have been prepared, the anthropologist compiles the biological profile of the individual: the assessment and determination of age, sex, ancestry and stature. 283. Age: This is estimated within a range, and is not exact. The older the individual, the wider the range. From the foetal stage to approximately 25 years of age, the human skeleton undergoes continuous development and growth. Several indicators are evaluated, including dentition development, length of long bones and the appearance and fusion of epiphyses in early ages; and, in later stages of development, the pubic symphysis and the morphology of the sternal end of the fourth rib. Once development stops, degenerative changes begin to appear, especially in the joints, such as signs of osteoarthritis (e.g. osteophytes). 284. Sex: The sexual dimorphism in the skeleton is seen after puberty, so before that period determination of sex is not very reliable. In older individuals, there are two main ways to determine the sex: (a) Morphological traits in specific areas of the pelvis and skull, and (b) Metric assessments, which involve measurements of various dimensions of limb bones and articular surfaces In cases where the remains are fragmented or no bones diagnostic of sex are available, a genetic analysis (amelogenin) could also be applied to determine the sex. Determining the sex (amelogenin) is undertaken as standard in the genetic analysis of bones. 285. Ancestry: Ancestry refers to the geographic region and/or the ancestral origin of a particular population group. It is assessed by evaluating specific traits in the skeleton, mainly in the skull, that can be present or absent, or present to some degree. At the same time, several measurements can be taken in the skull and post-cranial skeleton. Software is available to process the measurements and produce an assessment of the ancestry of the skeleton under analysis, when appropriate.