RETRACTED: Genotyping strategies for tissues fixed with various embalming fluids for human identification,...

Area of Science:

• Forensic Science
• Molecular Biology
• Anatomical Sciences

Background:

• Anatomical willed body programs rely on tracking mechanisms for identification.
• Failure of tracking necessitates alternative methods like DNA recovery from fixed tissues.
• Embalming fluids, while preserving tissues, can degrade DNA and proteins.

Purpose of the Study:

• To investigate the success of Short Tandem Repeat (STR) typing from formalin-fixed soft tissue and bone samples.
• To assess the impact of varying formaldehyde concentrations on DNA quality for identification.
• To determine optimal tissue sources and fixation strategies for DNA analysis in body donor programs.

Main Methods:

• Collected formalin-fixed tissue samples (skin, muscle, bone, heart, kidney) from cadavers.
• Extracted DNA using QIAamp® FFPE Tissue Kit and quantified with Investigator® QuantiPlex® Pro RGQ qPCR Kit.
• Amplified DNA using Investigator® 24plex, 26plex QS, and DIPplex Kits for STR-typing.

Main Results:

• DNA recovered from formalin-fixed tissues was severely damaged, degraded, and often in low quantities after one year.
• Skin and muscle tissues fixed with approximately 2.5%-5% formaldehyde yielded the most successful STR-typing results.
• These tissues maintained better preservation for identification purposes.

Conclusions:

• DNA analysis from formalin-fixed tissues is feasible but challenging due to degradation.
• Sampling skin and muscle from tissues fixed with moderate formaldehyde concentrations (2.5%-5%) is recommended for identification.
• This research provides data for optimizing genotyping strategies for formalin-fixed human remains in provenance databases.