How to store the bone powder left after extraction for future analysis

Area of Science:

• Forensic Science
• Molecular Biology
• Genetics

Background:

• Proper DNA preservation is crucial for forensic analysis.
• Bones are a common source of ancient DNA, typically stored frozen.
• Unused bone powder from DNA extraction requires optimal long-term storage.

Purpose of the Study:

• To evaluate the efficacy of room temperature storage for bone powder DNA preservation.
• To compare DNA quality and STR profile success between frozen and room temperature storage.
• To determine if freezing is necessary for long-term bone powder storage.

Main Methods:

• Selected 21 Second World War bone samples for DNA extraction.
• Stored resulting bone powder at -20°C (freezer) and room temperature for 3 years.
• Extracted DNA annually using a commercial kit and automated purification; quantified DNA via real-time PCR; assessed STR genotyping success.

Main Results:

• No significant differences in DNA quantity or degradation rates were observed between frozen and room temperature storage.
• High-quality short tandem repeat (STR) profiles were successfully generated from all samples after 3 years, irrespective of storage condition.
• Bone powder DNA integrity was maintained equally well at room temperature and in a freezer.

Conclusions:

• Freezing bone powder for long-term DNA preservation is unnecessary.
• Room temperature storage offers a cost-effective and space-saving alternative for bone powder.
• This simplifies DNA sample management in forensic science and research.