Bone Marrow as a Source of DNA in Forensic Genetics: An Optimized Nucleic Acids Extraction Protocol.

Area of Science:

• Forensic genetics
• Molecular biology
• Biochemistry

Background:

• Low-quantity or degraded samples are common in forensic genetics.
• Bone marrow, particularly putrefied or lipid-rich, presents extraction challenges due to its composition.
• Efficient DNA extraction is crucial for reliable forensic analysis.

Purpose of the Study:

• To develop an optimized nucleic acid extraction protocol for putrefied bone marrow.
• To improve DNA yield and quality from challenging forensic samples.
• To address limitations in current extraction methods for lipid-rich and degraded tissues.

Main Methods:

• Developed an optimized protocol by modifying a commercial silica-based column kit with additional steps, reagents, and time.
• Compared the optimized method against a standard protocol using putrefied human bone marrow from various decomposition stages.
• Evaluated DNA typing efficiency through real-time PCR quantification, Short Tandem Repeats (STR) amplification, and fragment analysis.

Main Results:

• The optimized protocol demonstrated significant improvements in allele count and DNA concentration compared to the standard protocol.
• Qualitative and quantitative enhancements suggest greater reliability for forensic casework.
• The protocol shows potential for routine application in forensic genetics.

Conclusions:

• The optimized protocol offers a viable solution for processing tough, lipid-rich tissues like putrefied bone marrow.
• It can be implemented without specialized equipment, using existing commercial kits.
• Further laboratory validation is recommended before routine forensic use.