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Bones or not ?

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Archana Mahakalkar

This document discusses methods for determining whether fragmented bone material is human or non-human. It outlines gross morphological differences visible to the naked eye, such as fused epiphyses in juvenile human long bones versus curved long bones in small mammals. Microscopic examination can reveal larger Haversian systems in human bone. Serological tests like precipitin reactions and collagen fingerprinting extract protein signatures to identify the species. DNA analysis of conserved mitochondrial RNA regions can also determine if a bone sample is human.

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Dr.Archana Mahakalkar Assistant Professor, Department of Forensic Biology Govt.Institute of Forensic Science,Nagpur
Module 2 Bones or not?
Introduction We can recognize bones as part of a complete skeleton. Most of us can recognize individual intact bones also. The recognition task becomes more difficult if we are faced with fragmented bones. Many common materials, such as plastic or pieces of tree root, have been confused with bone. A fragment of cranial vault bone can be confused with turtle shell.
Methods:
1. Gross Examination Human bone Non human bone Juvenile human long bone have separate epiphysis or may not posses all. A small adult non human animal will display fused epiphysis. Long bone is straight in human Long bone shaft of small mammals be noticeably curved. Human juvenile pelvis size is still in multiple pieces. Small pelvis is fused in one unit in non- human pelvis. a. Human child pelvis b. Pelvis of raccoon Book: Forensic Recovery of Human Remains
Continue.. Fibula does not normally fuse to the tibia unless there is pathology such as ossification of ligaments. In small animals including mammals the fibula is reduced in size and is fused to shaft of the tibia . Radius- ulna have straight diaphysis remain unfused thought life. Some larger mammals species eg. Pig, sheep, deer have a curved and fused radius-ulna. Human bone Non human bone Link.springer.com en.wikipedia.org
Continue.. (A) Bear foot (B) human foot. The human foot is a right foot; the bear foot is a left foot. Both are viewed from above.
Continue.. Bones on left are a bears paw. The hand on right is of human Source:The Use of Forensic Anthropology, Second Edition
Cross section of Human and Non- Human bone(Humerus) Cortex-Hard Compact bone Cancellous- spongy bone centre Large mammal (1/3) Human (1/4) Bird (1/8)
2. Microscopic examination Microscopic examination revels true Haversian systems and presence of osteons in human larger in diameter than animal. Microscopic sections of A. cow and B. human cortical bone. The arrows indicate Haversian systems in the human bone.
3. Serological Examination Precipitin test can be done by extracting species specific protein from bone tested against specific antisera of human. For this the techniques like gel diffusion and electrophoresis can be used. The technique, known as collagen fingerprinting, allows scientists to visualize distinct chemical signatures in collagen, the main structural protein in bone, that are often species-specific.
Human antisera Other species sera Bone extract Precipitate line Gel diffusion Fig: Precipitin test
Finally it is possible to determine if a piece of bone is human or not through an analysis of DNA . Studies have achieved success at species identification through test of highly conserved regions of mitochondrial 12S and 16S ribosomal RNA .(yang et.al.2014)
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Bones or not ?

  • 1. Dr.Archana Mahakalkar Assistant Professor, Department of Forensic Biology Govt.Institute of Forensic Science,Nagpur
  • 2. Module 2 Bones or not?
  • 3. Introduction We can recognize bones as part of a complete skeleton. Most of us can recognize individual intact bones also. The recognition task becomes more difficult if we are faced with fragmented bones. Many common materials, such as plastic or pieces of tree root, have been confused with bone. A fragment of cranial vault bone can be confused with turtle shell.
  • 5. 1. Gross Examination Human bone Non human bone Juvenile human long bone have separate epiphysis or may not posses all. A small adult non human animal will display fused epiphysis. Long bone is straight in human Long bone shaft of small mammals be noticeably curved. Human juvenile pelvis size is still in multiple pieces. Small pelvis is fused in one unit in non- human pelvis. a. Human child pelvis b. Pelvis of raccoon Book: Forensic Recovery of Human Remains
  • 6. Continue.. Fibula does not normally fuse to the tibia unless there is pathology such as ossification of ligaments. In small animals including mammals the fibula is reduced in size and is fused to shaft of the tibia . Radius- ulna have straight diaphysis remain unfused thought life. Some larger mammals species eg. Pig, sheep, deer have a curved and fused radius-ulna. Human bone Non human bone Link.springer.com en.wikipedia.org
  • 7. Continue.. (A) Bear foot (B) human foot. The human foot is a right foot; the bear foot is a left foot. Both are viewed from above.
  • 8. Continue.. Bones on left are a bears paw. The hand on right is of human Source:The Use of Forensic Anthropology, Second Edition
  • 9. Cross section of Human and Non- Human bone(Humerus) Cortex-Hard Compact bone Cancellous- spongy bone centre Large mammal (1/3) Human (1/4) Bird (1/8)
  • 10. 2. Microscopic examination Microscopic examination revels true Haversian systems and presence of osteons in human larger in diameter than animal. Microscopic sections of A. cow and B. human cortical bone. The arrows indicate Haversian systems in the human bone.
  • 11. 3. Serological Examination Precipitin test can be done by extracting species specific protein from bone tested against specific antisera of human. For this the techniques like gel diffusion and electrophoresis can be used. The technique, known as collagen fingerprinting, allows scientists to visualize distinct chemical signatures in collagen, the main structural protein in bone, that are often species-specific.
  • 13. Finally it is possible to determine if a piece of bone is human or not through an analysis of DNA . Studies have achieved success at species identification through test of highly conserved regions of mitochondrial 12S and 16S ribosomal RNA .(yang et.al.2014)