Age estimation based on aspartic acid racemization in elastin from the yellow ligaments

Area of Science:

• Biochemistry
• Forensic Anthropology
• Biomolecular Analysis

Background:

• Yellow ligaments possess high elastin content, a protein known for its stability.
• This stability suggests potential for using yellow ligaments in age estimation techniques.
• Aspartic acid racemization (AAR) is a biochemical process sensitive to aging in proteins.

Purpose of the Study:

• To evaluate the efficacy of aspartic acid racemization (AAR) in yellow ligaments for age estimation.
• To compare AAR kinetics in total ligament tissue versus purified elastin.
• To determine the reliability of AAR in purified elastin for forensic age assessment.

Main Methods:

• Collected yellow ligament samples from individuals of known age.
• Determined AAR levels in both whole ligament tissue and purified elastin.
• Analyzed the correlation between AAR values and chronological age.

Main Results:

• AAR levels increased with age in both total tissue and purified elastin samples.
• Purified elastin showed significantly faster AAR kinetics (3.7-4.6 times higher rates).
• A strong correlation between AAR and age was observed in purified elastin (r=0.96-0.99).

Conclusions:

• AAR in purified spinal yellow ligament elastin is a reliable method for biochemical age estimation.
• Analysis of total ligament tissue is not recommended due to collagen variability.
• This method offers a valuable tool for identifying unidentified cadavers when other methods fail.