Optimization of InnoXtract™ extraction and purification system for DNA extraction from skeletal samples

Area of Science:

• Forensic Science
• Molecular Biology
• Genetics

Background:

• The InnoXtract™ system is designed for DNA extraction from low-template samples like rootless hair.
• Its ability to capture fragmented DNA suggests potential for challenging samples such as skeletal remains.
• Optimization of lysis and digestion parameters was necessary for skeletal sample application.

Purpose of the Study:

• To modify and validate the InnoXtract™ system for efficient DNA extraction from diverse skeletal remains.
• To assess the quality and quantity of DNA recovered using the optimized protocol.
• To evaluate the suitability of the extracted DNA for generating short tandem repeat (STR) profiles.

Main Methods:

• A two-part digestion protocol was developed using a homebrew buffer (0.5 M EDTA, 0.05% Tween 20, 100 mM NaCl) and the InnoXtract™ Hair Digestion Buffer.
• Magnetic bead volume was adjusted to enhance DNA recovery from skeletal samples.
• The modified InnoXtract™ protocol was compared against a commercial skeletal extraction kit (PrepFiler™ BTA).

Main Results:

• The modified InnoXtract™ protocol yielded DNA comparable in quality and quantity to the PrepFiler™ BTA kit.
• Sufficient high-quality DNA was purified from various skeletal sample types, including surface decomposition, burned, cremated, buried, and embalmed remains.
• Complete STR profiles were successfully generated from the extracted DNA.

Conclusions:

• The optimized InnoXtract™ system provides a viable method for DNA extraction from challenging skeletal samples.
• This method shows significant potential for applications in human identification and missing-person investigations.
• The protocol's adaptability to diverse and degraded skeletal remains enhances its utility in forensic casework.