Petrous Bone
Definition
The petrous portion of the temporal bone, the densest bone in the human skull. Its dense hydroxyapatite matrix protects enclosed DNA from environmental degradation. Consistently the highest-yield site for ancient and forensic DNA when soft tissue and other skeletal elements are too degraded to profile.
- Location
- Part of the temporal bone at the skull base, encasing the inner ear
- Key property
- Highest mineralization density of all skeletal elements
- Primary use
- Preferred DNA sampling site in degraded or commingled remains
Common questions
Why is the petrous bone preferred for DNA recovery?+
The petrous bone has the highest mineralization density of any bone in the skeleton, which shields DNA from degradation over time. This makes it the best choice when working with old or severely degraded remains.
What is the petrous bone and where is it located?+
It is the dense, pyramid-shaped portion of the temporal bone that forms part of the skull base. It houses the inner ear structures and is one of the most robust parts of the skeleton.
In what forensic situations is the petrous bone most useful?+
It is especially valuable in mass-disaster victim identification (DVI) and ancient DNA casework, where skeletal remains may be heavily compromised. Its superior DNA yield makes it the preferred site when multiple bones are available.
Related terms
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- Autolysis
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- Biological Profile
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- Commingled Remains
- Skeletal material from more than one individual mixed together, as commonly recovered from mass graves, transportation disasters, or fire scenes. Sorting commingled...
- D-Loop
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- DVI (Disaster Victim Identification)
- The systematic multi-agency process for identifying victims of mass-casualty events, governed by the INTERPOL DVI Guide 2018 revision. Organises work into five...
- EDTA Decalcification
- Demineralisation of bone powder using 0.5 M EDTA at pH 8.0, which chelates calcium from hydroxyapatite and releases DNA from the mineral...
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- Heteroplasmy
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- ICMP (International Commission on Missing Persons)
- The international organisation that has led DNA-based identification of missing persons from the former Yugoslavia since 1996, working from a laboratory in...
Explained in these topics
- DVI from the Osteology Angle: MNI, MNE and the Commingled-Remains ProblemThe dense pyramidal portion of the temporal bone encasing the inner ear. Consistently yields the highest DNA concentrations in degraded skeletal remains due to...
- Soft Tissue Preservation and DecompositionThe petrous portion of the temporal bone, the densest bone in the human skull. Its dense hydroxyapatite matrix protects enclosed DNA from environmental degrada...
- The Cell, the Nucleus and the Mitochondrion as DNA ReservoirsThe dense pyramid-shaped portion of the temporal bone forming part of the skull base. Highest mineralisation density of any skeletal element correlates with su...
- Touch DNA, Hair, Bone, Teeth and Challenging SubstratesThe dense portion of the temporal bone of the skull. The preferred skeletal sampling site for DNA recovery in DVI and ancient DNA work because its mineralisati...